Subtitute for a Variable - Definition & Examples
Read this topicExplanations 3
- (Video) Substituting Numbers for a Variable by Skarinsensei Here's a video by Skarinsensei that shows you what to do when substituting a number into a variables place. Summary\l…
By Alex Federspiel, Amy Feraco, Jonathan Heller, Anusha Rahman
- Substitution is an essential part of solving equations for variables. Variables (like xxx, yyy, zzz) are stand-ins for constants (−4-4−4, 23\frac{2}{3}32, π\piπ), plugging the …
By Liza Sulkin, Amy Feraco, Jonathan Heller, Alex Federspiel, Anusha Rahman
- If we think back to the definition of variable, we know that it's a placeholder for numeric values. Generally, a variable can take on a range of values, unless otherwise specifi…
By Anusha Rahman
Problems 25
- Solve equation (A) and plug the result into expression (B). y−2=3(A)3x−1(B)\begin{array}{lc} y-2=3&\quad\small{(A)}\\ 3x-1&\quad\small{(B)} \end{array}y−2=33x−1(A)(B)
- Solve equation (A) and plug the result into expression (B). 2x=4(A)2x(B)\begin{array}{lc} 2x=4&\quad\small{(A)}\\ 2x&\quad\small{(B)} \end{array}2x=42x(A)(B)
- Solve equation (A) and plug the result into expression (B). xx−6=2(A)6x2−x(B)\begin{array}{lc} \frac{x}{x-6}=2&\quad\small{(A)}\\ \frac{6}{x^2-x}&\quad\small{(B)} \end{array}x−6…
- Solve equation (A) and plug the result into expression (B). 23−6x8=12(A)45+35x(B)\begin{array}{lc} \frac{2}{3}-\frac{6x}{8}=\frac{1}{2}&\quad\small{(A)}\\ \frac{4}{5}+\frac{3}{5…
- Solve equation (A) and plug the result into expression (B). 2x+44=3(A)5x+46(B)\begin{array}{lc} \frac{2x+4}{4}=3&\quad\small{(A)}\\ \frac{5x+4}{6}&\quad\small{(B)} \end{array}42…
- For the equations 3x+9=63x+9=63x+9=6 and 14x+27=□14x+27=\square14x+27=□ to be equivalent, what number should be filled in the square, □\square□?
- Will the xxx in (1)(1)(1) be equal to the xxx in (2)(2)(2)?
- Solve equation (A) and plug the result into expression (B). x+18=372(A)6−2xx(B)\begin{array}{lc} x+18=\frac{37}{2}&\quad\small{(A)}\\ \frac{6-2x}{x}&\quad\small{(B)} \end{array}…
- Solve equation (A) and plug the result into expression (B). x3=8(A)x2(B)\begin{array}{lc} x^3=8&\quad\small{(A)}\\ \sqrt{x^2}&\quad\small{(B)} \end{array}x3=8x2(A)(B)
- Solve equation (A) and plug the result into expression (B). 14xx=2x(A)3x−9(B)\begin{array}{lc} \frac{14x}{x}=2x&\quad\small{(A)}\\ 3x-9&\quad\small{(B)} \end{array}x14x=2x3x−9…
- Solve equation (A) and plug the result into expression (B). 4x=12(A)x2−2x(B)\begin{array}{lc} \frac4x=\frac12&\quad\small{(A)}\\ \frac x2-\frac2x&\quad\small{(B)} \end{array}x4…
- Solve equation (A) and plug the result into expression (B). 2x+3=9(A)x+1(B)\begin{array}{lc} 2x+3=9&\quad\small{(A)}\\ \sqrt{x+1}&\quad\small{(B)} \end{array}2x+3=9x+1(A)(B)
- Solve equation (A) and plug the result into expression (B). 14x−6=12(A)143x+1(B)\begin{array}{lc} 14x-6=12&\quad\small{(A)}\\ \frac{14}3x+1&\quad\small{(B)} \end{array}14x−6=123…
- Solve equation (A) and plug the result into expression (B). 3x−1=6(A)4x+2(B)\begin{array}{lc} 3x-1=6&\quad\small{(A)}\\ 4x+2&\quad\small{(B)} \end{array}3x−1=64x+2(A)(B)
- Solve equation (A) and plug the result into expression (B). 100x+99x+98x+⋯+2x+x=10100(A)100−x(B)\begin{array}{lc} 100x+99x+98x+\dots+2x+x=10100&\quad\small{(A)}\\ 100-x&\quad\sm…
- Solve equation (A) and plug the result into expression (B). x(2+3)=3(A)23−x(B)\begin{array}{lc} x(2+\sqrt3)=\sqrt3&\quad\small{(A)}\\ 2\sqrt3-x&\quad\small{(B)} \end{array}x(2+3…
- Solve equation (A) and plug the result into expression (B). 2+1x=4(A)9x(B)\begin{array}{lc} 2+\frac1x=4&\quad\small{(A)}\\ 9^x&\quad\small{(B)} \end{array}2+x1=49x(A)(B)
- Solve equation (A) and plug the result into expression (B). x+2−3x+6=x(A)3+x(B)\begin{array}{lc} x+2-3x+6=x&\quad\small{(A)}\\ 3+x&\quad\small{(B)} \end{array}x+2−3x+6=x3+x(A)(B)
- Solve equation (A) and plug the result into expression (B). 3x=68(A)81x(B)\begin{array}{lc} \frac3x=\frac68&\quad\small{(A)}\\ \sqrt[x]{81}&\quad\small{(B)} \end{array}x3=86x8…
- Solve equation (A) for yyy and plug the result into expression (B). 3cosx−3y=6(A)4cosx−8y(B)\begin{array}{lc} 3\cos x-3y=6&\quad\small{(A)}\\ \frac{4\cos x-8}{y}&\quad\small{(…
- Solve for xxx in the first equation and substitute that into the second equation to solve for yyy. 2x=4x+y=52x=4\\ x+y=52x=4x+y=5
- What is the value of xxx? y2=5y2+x=6y^2=5\\ y^2+x=6y2=5y2+x=6
- Solve equation (AAA) and plug the result into expression (BBB). y−2=3(A)y(B)\begin{array}{lc} y-2=3&\quad\small{(A)}\\ y&\quad\small{(B)} \end{array}y−2=3y(A)(B)
- Solve equation (A) and plug the result into expression (B). x=9(A)7x−6(B)\begin{array}{lc} x=9&\quad\small{(A)}\\ 7x-6&\quad\small{(B)} \end{array}x=97x−6(A)(B)
- Solve equation (A) and plug the result into expression (B). x=300y+17z−11w(A)a(B)\begin{array}{lc} x=300y+17z-11w&\quad\small{(A)}\\ a&\quad\small{(B)} \end{array}x=300y+17z−11w…