You can soustracte the first or the second one
and y cancel
x = 6
now you put 6 in x
you can take the first or the second one
6 - y = -2
6 - y = -2
y = -8
3n+(4n-15)=90
3n+4n-15=90
7n=105
n=105/7
n=15
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Angle LQK is 4n-15
If n=15
Angle LQK = 4(15) - 15
= 60 - 15
= 45
Answer:
-5
2.45×10
2.45×103
2.45×107
Step-by-step explanation:
-5=5
2.45×10=24.5
2.45×103=252.35
2.45×107=262.15
Answer:
Step-by-step explanation:

Subtract 4 times the first equation from the second:
(-7y +16x -80) -4(-9y +4x -20) = (0) -4(0)
29y = 0 . . . . . simplify
y = 0 . . . . . . . .divide by 29
4x -20 = 0 . . . . substitute 0 for y in the first equation
x -5 = 0 . . . . . .divide by 4
x = 5 . . . . . . . . add 5
The solution to this system is (x, y) = (5, 0).