Question

resolva com o método da Operação inversa

A)
2a/3 + a/5 =26

B)
R- r/4 = 3/2

Answer 1

A) 2a/3 + a/5 =26

$2\cdot \frac{a}{3}+\frac{a}{5}=26\quad :\quad a=30\\\\\\\\2\cdot \frac{a}{3}+\frac{a}{5}=26\\\\2\cdot \frac{a}{3}+\frac{a}{5}:\quad \frac{13a}{15}\\\\\\\frac{13a}{15}=26\\\\\frac{13a}{15}\cdot \:15=26\cdot \:15\\\\13a=390\\\\\frac{13a}{13}=\frac{390}{13}\\\\a=30$

B) R- r/4 = 3/2

$r-\frac{r}{4}=\frac{3}{2}\quad :\quad r=2\\\\r\cdot \:4-\frac{r}{4}\cdot \:4=\frac{3}{2}\cdot \:4\\\\4r-r=6\\\\3r=6\\\\\frac{3r}{3}=\frac{6}{3}\\\\r=2$

espero ter ajudado fofo: