X+ y = 2....multiply by -2
2x + 5y = 16
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-2x - 2y = -4 (result of multiplying by 2-)
2x + 5y = 16
-------------add
3y = 12
y = 12/3
y = 4
x + y = 2
x + 4 = 2
x = 2 - 4
x = -2
solution is (-2,4)
18=3(2x-6)
Multiply the bracket by 3
18=3(2x)(3)(-6)
18=6x-18
Move -18 to the other side. Sign changes from -18 to +18.
18+18=6x-18+18
18+18=6x
36=6x
Divide by 6 for both sides.
36/6=6x/6
x=6
Answer: x=6
Answer: Constant
No matter what the input x is, the output f(x) is going to be -4. Therefore, the output is constant.
Note: f(x) can be interchanged with y. So we can say y = -4.
Just find the slope between the points
basically find (f(10)-f(7))/(10-7)
f(7)=7^2-3(7)-4=49-21-4=24
f(10)=10^2-3(10)-4=100-30-4=66
slope=(66-24)/(10-7)=42/3=14
average rate of change is 14