Question

Solveeee both i neeeeeedddd hellllpppp

Answer 1

Short answer: C
Remark
Since b is all by itself in equation 2, Substitute it into equation 1.

2a + 3b = 5
b = a - 5                       Put this result in equation 1. Be sure and use brackets.
2a + 3(a - 5) = 5          Remove the brackets.
2a + 3a - 15 = 5           Notice the -5 inside the brackets becomes - 15
                                    Combine like terms on the left.    
5a - 15 = 5                   Add 15 to both sides
5a = 5 + 15
5a = 20                        Divide by 5
a = 20/5
a = 4

So far, c is the only possible answer.
b = a - 5
b = 4 - 5
b = - 1