Answer:
D
Step-by-step explanation:
The 3 consecutive numbers are 88, 89, and 90. So 90 is the answer.
Answer:
y= -2x²+4x.
Step-by-step explanation:
the common equation of the parabola is y=ax²+bx+c, where a, b, c - numbers.
1) the coordinates of the vertex are:

2) if according to the condition x₀=1, then b= -2a.
If according to the condition y₀=2, then 
it means that c=a+2.
3) if b= -2a; c=a+2 and the point (3;-6) belongs to the given parabola, then it is possible to substitute them into the common equation of the parabola:
-6=3²*a-6a+a+2; ⇔ a= -2.
4) if a= -2, then b=-2a=4, and c=a+2=0.
5) if a=-2, b=4 and c=0, then the required equation of the parabola is:
y= -2x²+4x.
Answer:
x = -6/5
y =7/5
Step-by-step explanation:
2x + y = - 1
x - 2y = - 4
Multiply the first equation by 2 so we can eliminate y
2(2x + y = - 1)
4x + 2y = -2
Add this to the second equation
4x + 2y = -2
x - 2y = - 4
---------------------
5x + 0y = -6
Divide by 5
5x/5 = -6/5
x = -6/5
Multiply the second equation by -2 so we can eliminate x
-2(x - 2y = - 4)
-2x+4y = 8
Add this to the first equation
2x + y = - 1
-2x+4y = 8
---------------------
0x + 5y = 7
Divide by 5
5y/5 = 7/5
y =7/5