Answer:
y = -2(x + 1)^2 + 8
Step-by-step explanation:
The equation of a parabola can be written in the form;
y = a(x-h)^2 + k
where a is the multiplier (h,k) is the vertex
so h = -1 and k = 8
Plug in these values
y = a(x + 1)^2 + 8
So to get the value of a, we use the point where the parabola passes through which is the point (1,0)
Simply substitute the values of x and y
0 = a(1 + 1)^2 + 8
0 = a(2)^2 + 8
-8 = 4a
a = -8/4
a = -2
So therefore the equation of the parabola is ;
y = -2(x + 1)^2 + 8
The vertex point is (0,4)
The two other points are (-2,0)(2,0)
Answer:
x ≈ 3.1 ft
Step-by-step explanation:
The segment from the centre to the chord is a perpendicular bisector, thus
The triangle is right with base = 
x
Applying Pythagoras' identity to the right triangle, then
( x )² + 1.4² = 2.1²
x² + 1.96 = 4.41 ( subtract 1.96 from both sides )
x² = 2.45 ( multiply both sides by 4 )
x² = 9.8 ( take the square root of both sides )
x = 
≈ 3.1 ft ( to the nearest tenth )
A negative exponent is the opposite of a regular exponent so for example, 5 to the power of -3 is 1/125
