Answer:
1. (-2,3)
2. (1.5,-4)
3. (1, -7)
4. (-15/9,33/9)
5. (-2,-1)
6. (-18/11,92/11)
7. (1,-3)
8. (8,8)
Step-by-step explanation:
1. y = -3x - 3 = 7x + 17
7x + 3x = -3 - 17
10x = - 20
x = -2
y = -3x - 3 = -3(-2) - 3 =6 - 3 = 3
2. y = -4x + 2
- 8x - 4y = -8 => y = (8x - 8)/4 = 2x - 2
so -4x + 2 = 2x - 2
2x + 4x = 2 + 2
6x = 4
x = 1.5
y = -4x + 2 = -4(1.5) + 2 = -4
3. y = 7x - 14 and y = -7x
7x - 14 = -7x
7x + 7x = 14
14x = 14
x = 1
y = -7(1) = -7
4. y = 2x + 7 and y = 7x + 22
so 2x + 7 = 7x + 22
7x - 2x = 7 - 22
9x = -15
x = -15/9
y = 2(-15/9) + 7 = -30/9 + 7 = 33/9
5. y = -2x - 5 and -8x + 2y = 14 => y = (8x + 14)/2 = 4x + 7
so -2x - 5 = 4x + 7
4x + 2x = -5 - 7
6x = -12
x = -2
y = 4(-2) + 7 = -8 + 7 = -1
6. -2x - 7y = 16 => 7y = 2x + 16 => y = (2x + 16)/7
y = -6x - 8
so -6x - 8 = (2x + 16)/7
-42x - 56 = 2x + 16
2x + 42x = - 56 - 16
44x = - 72
x = -72/44 = -18/11
y = -6x - 8 = -6(-18/11) - 8 = 180/11 - 88/11 = 92/11
7. x - 7y = - 10 => x = 7y - 10
- x + 5y = 8 => x = 5y - 8
so 7y - 10 = 5y - 8
7y - 5y = 10 - 8
2y = 2
y = 1
- x + 5(1) = 8
x = 5 - 8 = -3
8. - x + 4y = 24 => y = (x + 24)/4
-2x + y = -8 => y = 2x - 8
so (x + 24)/4 = 2x - 8
x + 24 = 8x - 32
8x - x = 24 + 32
7x = 56
x = 8
y = 2x - 8 = 2(8) - 8 = 16 - 8 = 8
I hope I got all the answers correct. Let me know if I missed anything
