Step-by-step explanation:
for some reason the equation at the top says 7(x+2) but both of the equations at the bottom say 7(x-2)... I'm just going to do 7(x-2)
Emmanuels Work:
7(x-2)=91
distribute the 7 by multiplying both x and -2 by it
7x-14=91
add 14 to both sides
7x=105
divide both sides by 7
x=15
Mauricio's Work:
7(x-2)=91
to get rid of the 7 multiplication, divide both sides by 7
x-2=13
add 2 to both sides
x=15