Question

The equations were multiplied by constants and added together to determine that the value of x in the system of equations is –20. One-fifth x minus one-third y = negative 1 Negative three-fourths x + one-third y = 12 What is the value of y? –15 –9 9 15

Answer 1

Answer:

Step-by-step explanation:

Given:

1. 1/5x - 1/3y = -1

2. -3/4x +1/3y = 12

Multiplying equation 1 by 15 and equation 2 by 12

3. 3x - 5y = -15

4. -9x + 4y = 144

and then Solving both equations simultaneously, since x = -20 as stated in the question and by confirmation,

Using equation 3 or 4 to solve for y,

3(-20) - 5y = -15

-5y = 60 - 15

y = 45/-5

= -9

y = -9