Question

Consider the system of equations:
−
7
15
x
+
2
5
y
=
1
3

1.05
x
−
3.15
y
=
−
6.3
Is the ordered pair
(
−
15
7
,
4
7
)
a solution to this system?
Select one answer
A
No, because the ordered pair satisfies the first equation but not the second equation.

B
No, because the ordered pair satisfies the second equation but not the first equation.

C
No, because the ordered pair does not satisfy either equation.

D
Yes, because the ordered pair satisfies both equations.

Answer 1

C

Check both equations with x = -15/7, y = 4/7.

1) -7/15·x + 2/5·y = -7/15·(-15/7) + 2/5·(4/7) = 1 + 8/35 = 43/35 ≠ 1/3.

2) 1.05·x - 3.15·y = 1.05·(-15/7) - 3.15·(4/7) = -2.25 - 1.8 = -4.05 ≠ -6.3.

So the pair satisfies neither equation.