Question

If 2a=3b and 4a+b=21, then b =

Answer 1

b=3

Explanation:

2a=3b and 4a+b=21,

Multiply the first equation by 2

2(2a) = 2*3b

4a = 6b

Substitute this into the second equation

4a+b = 21

Replace 4a with 6b

6b+b = 21

Combine like terms

7b = 21

Divide each side by 7

7b/7 = 21/7

b = 3