Examine the system of equations. −5x + 5y = 40 4x + 3y = 24 What is the solution?

2 answers:

3 0

-5x + 5y = 40 -20x +20y =160 -5x + 5(8) = 40
4x + 3y = 24 20x +15y =120 -5x + 40 = 40
35y = 280 -5x =0
y = 8 x = 0

Hope you understood this

densk [106]3 years ago

3 0

The solution is (0,8). I solved this system of equations by using substitution.

1). -5x + 5y = 40
+ 5x + 5x
----------------------------------
5y = 5x + 40
------- ---- ------
5 5 5

y = x + 8

__________________________________________________________

2). 4x + 3(x + 8) = 24
4x + 3x + 24 = 24

7x + 24 = 24
- 24 -24
-----------------------
7x = 0
---- ----
0 0

x = 0
__________________________________________________________

3). -5(0) + 5y = 40

0 + 5y = 40

5y = 40
---- ------
5 5

y = 8
__________________________________________________________

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