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? What is the solution of a system defined by 5x + 2y = 30 and -5x + 4y = 0? 0 (0, 30) O (6, 15) O (4,5) 0 (6,0)​

User DeTeReR
by
3.0k points

1 Answer

3 votes

Answer:

(4,5)

Explanation:

Hi there!

We are given the system of equations:

5x+2y=30

-5x+4y=0

and we need to find the solution

there are 3 ways to solve a system of equations, but let's use the elimination method, where we will add the systems together to clear one variable out, solve for the other variable, and use the value of the solved variable to find the other variable

When we clear a variable, the coefficients need to be opposites (ex. 2 and -2). In this case, the coefficients in front of x are 5 and -5 in the first and second equation respectively

5x+2y=30

-5x+4y=0

add the equations together

6y=30

divide both sides by 6

y=5

we found the value of y

now we need to find the value of x

substitute 5 as y into either one of the equations (ex. the first one) to solve for x

5x+2(5)=30

multiply

5x+10=30

subtract 10 from both sides

5x=20

divide both sides by 5

x=4

so the answer is x=4, y=5; as a point, it's (4,5)

Hope this helps! :)

User Matt Wilding
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3.4k points