The value of x and y in the equation -5x + 8y = -21 and 3x - 4y = 15 are 9 and 4 respectively.
<h3>What is an equation?</h3>
An equation is the statement that illustrates that the variables given. In this case, two or more components are taken into consideration to describe the scenario. It is vital to note that an equation is a mathematical statement which is made up of two expressions that are connected by an equal sign.
The equation is given as:
-5x + 8y = -21
3x - 4y = 15
Multiply equation i by 3
Multiply equation ii by 5
-15x + 24y = -63
15x - 20y = 75
Add both equations
4y = 12
Divide
y = 12/4
y = 3
From 3x - 4y = 15
3x - 4(3) = 15
3x - 12 = 15
Collect like terms
3x = 12 + 15
3x = 27
Divide
x = 27/3
x = 9
Therefore, x = 9 and y = 4.
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