Question

[2 x (a-7) + 10] x 5 - 21=79 a=?

Answer 1

[2 x ( a-7) + 10 ] x 5 = 79+ 21
[2 x ( a-7) + 10 ] x 5 = 100
[2 x ( a-7) + 10 ] =$\frac{100}{5}$
[2 x ( a-7) + 10 ] =20
2 x ( a-7 ) = 20 - 10
2 x ( a - 7) = 10
2a - 14 =10
2a= 10+14
2a=24
a=$\frac{24}{2}$
a=12