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What is the solution to the system of equations?

3x+10y=-47
5x-7y = 40
O (1,-5)
O (1,5)
O (-1,-5)
O (-1,5)
HELPPPP

User Magomogo
by
5.3k points

1 Answer

6 votes

9514 1404 393

Answer:

(1, -5)

Explanation:

Here, it is easy to check the offered choices. We find the first one works, so our check is short.

For (x, y) = (1, -5)

3·1 +10·(-5) = 3 -50 = -47 . . . yes

5·1 -7·(-5) = 5 +35 = 40 . . . yes

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Both of the intercepts in the first equation are negative, so the line will form a triangle with the axes in the 3rd quadrant. The intercepts for the second equation are negative for y and positive for x, so the line forms a triangle with the axes in the 4th quadrant. The y-intercept for the first equation is -4.7; for the second equation, it is -40/7 = -5 5/7. This means the lines must cross in the 4th quadrant.

The only offered point in the 4th quadrant is (1, -5).

What is the solution to the system of equations? 3x+10y=-47 5x-7y = 40 O (1,-5) O-example-1
User Matthis Kohli
by
5.5k points