Question

How do I kno how to solve this equation either by substitution or elimination 3x = -31 +2y and 5x + 6y = 23? Please help me and explain how

Answer 1

Type in Wolfram Alpha into Google and put in the problem into the box

Answer 2

Are u serious or kidding me?

Answer 3

I would solve by elimination.

rearrange the first equation...
3x = -31 + 2y is the same as 3x - 2y = -31
5x + 6y = 23

so now we have :
3x - 2y = -31 -->(3)
5x + 6y = 23
---------------
9x - 6y = - 93 (result of multiplying by 3)
5x + 6y = 23
---------------add
14x = - 70
x = - 5

now sub -5 in for x in either of the original equations
3x - 2y = -31
3(-5) - 2y = -31
-15 - 2y = -31
-2y = -31 + 15
-2y = - 16
y = 8

check...
5x + 6y = 23
5(-5) + 6(8) = 23
-25 + 48 = 23
23 = 23 (correct)

x = -5 and y = 8

any questions ?

Answer 4

No thanx!!! :)

Answer 5

glad I could help :)