Find solutions to your problems with the help of IDNLearn.com's knowledgeable users. Get prompt and accurate answers to your questions from our community of experts who are always ready to help.

SOLVE ALL THESE EQUATION BY USING THE METHOD SUBSTITUTION ALGEBRAICALLY HERE'S ARE ALL THE EQUATION:
1. -7x - y = - 1/ y = 8x= 16
2. 3x +4y =0/ y=-3x -18
3. y = 3x/ -5x -2y = - 11
4. -8x -7y =0/ y = 6x
8. 2x- 6y = -14/ y=-5x -19


Sagot :

Answer:

See below ~

Step-by-step explanation:

Question 1

  • -7x - y = -1
  • y = 8x + 16

⇒ -7x - (8x + 16) = -1

⇒ -7x - 8x - 16 = -1

⇒ -15x = 15

⇒ x = -1

⇒ y = 8(-1) + 16 = 8

Solution = (-1, 8)

Question 2

  • 3x + 4y = 0
  • y = -3x - 18

⇒ 3x + 4(-3x - 18) = 0

⇒ 3x - 12x - 72 = 0

⇒ -9x = 72

⇒ x = -8

⇒ y = -3(-8) - 18 = 6

Solution = (-8, 6)

Question 3 (not clear)

Question 4

  • -8x - 7y = 0
  • y = 6x

⇒ -8x - 7(6x) = 0

⇒ -8x - 42x = 0

⇒ -50x = 0

⇒ x = 0

⇒ y = 6(0) = 0

Solution = (0, 0)

Question 8

  • 2x - 6y = -14
  • y = -5x - 19

⇒ 2x - 6(-5x - 19) = -14

⇒ 2x + 30x + 114 = -14

⇒ 32x = -128

⇒ x = -4

⇒ y = -5(-4) - 19 = 1

Solution = (-4, 1)