Solve the following system of equations by the substitution method.

8x = 2y + 5

3x = y + 7

what is the solution set?

{(-41/2, -9/2)}
{(-9/2, -41/2)}
ø

8x = 2y + 5
3x = y + 7

We will use the second equation to substitute in the first one. Here's how to do it:
3x = y + 7
y = 3x - 7 (now substitute this in the first equation)

8x = 2y + 5
8x = 2(3x - 7) + 5
8x = 6x - 14 + 5
8x = 6x - 9
6x - 9 = 8x
6x - 8x = 9
-2x = 9
x = -9/2 (this is the first coordinate, now we need to find y)

We use the second equation again:
3x = y + 7
y + 7 = 3x
y + 7 = 3(-9/2)
y + 7 = -27/2
y = -27/2 - 7
y = -27/2 - 14/2
y = -41/2 (this is the second coordinate)

This means that the solution set is the second option: {(-9/2, -41/2)}

38+105= 143, 39+104=143, and you will find then adding the numbers on opposite sides, moving inwards yields the answer 138 every time. because of this, you’re going to multiply 138 times the number of pairs, which is 34. therefore, 34*138= 4692(i’m sorry if it’s the wrong numbers, but it’s the right concept)