MATH SOLVE

2 months ago

Q:
# What is the solution to the above system of equations? 2x+5y=-4 4x-5y=22 A. (3,-2)B. (13/3, -24/3)C. (-2,3)D. (3,2/5)

Accepted Solution

A:

Answer: A. (3,-2)Step-by-step explanation:Solve by Substitution :
// Solve equation [2] for the variable x
[2] 4x = 5y + 22
[2] x = 5y/4 + 11/2
// Plug this in for variable x in equation [1]
[1] 2•(5y/4+11/2) + 5y = -4
[1] 15y/2 = -15
[1] 15y = -30
// Solve equation [1] for the variable y
[1] 15y = - 30
[1] y = - 2 // By now we know this much :
x = 5y/4+11/2
y = -2
// Use the y value to solve for x
x = (5/4)(-2)+11/2 = 3 Solution :
{x,y} = {3,-2}