Question

Resolva a equação literal 2x+2a=20, de incógnita

Answer 1

$2x+2a=20 \ \textgreater \ \mathrm{Subtract\:}2a\mathrm{\:from\:both\:sides} \ \textgreater \ 2x+2a-2a=20-2a$

$\mathrm{Simplify} \ \textgreater \ 2x=20-2a \ \textgreater \ \mathrm{Divide\:both\:sides\:by\:}2 \ \textgreater \ \frac{2x}{2}=\frac{20}{2}-\frac{2a}{2}$

$\frac{2x}{2} \ \textgreater \ \mathrm{Divide\:the\:numbers:}\:\frac{2}{2}=1 \ \textgreater \ x$

$\frac{20}{2}-\frac{2a}{2} \ \textgreater \ \mathrm{Apply\:rule}\:\frac{a}{c}\pm \frac{b}{c}=\frac{a\pm \:b}{c} \ \textgreater \ \frac{20-2a}{2}$

$20-2a \ \textgreater \ \mathrm{Rewrite\:as} \ \textgreater \ 2\cdot \:10-2a \ \textgreater \ \mathrm{Factor\:out\:common\:term\:}2$

$2\left(-a+10\right) \ \textgreater \ \frac{2\left(-a+10\right)}{2} \ \textgreater \ \mathrm{Divide\:the\:numbers:}\:\frac{2}{2}=1 \ \textgreater \ x = -a+10$

Hope this helps!