Answer:
y = (x - 4)² - 25
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
To obtain this form use the method of completing the square.
Given
y = (x + 1)(x - 9) ← expand factors using FOIL, thus
y = x² - 8x - 9
To complete the square
add/subtract ( half the coefficient of the x- term )² to x² - 8x
y = x² + 2(- 4)x + 16 - 16 - 9
= (x - 4)² - 25 ← in vertex form
Answer:
-15
Step-by-step explanation:
She must have multiplied it by 5.
That would've given her:
x - y = 15
2.5x + y = 25
Now we can add them and the y-terms will eliminate each other. Because one is -y, and the other is positive y. -y + y = 0.
Answer:
- The circumference of the circle in term of pi = 10π inches
- The circumference of the circle us 3.14 as pi = 31.4 inches
Step-by-step explanation:
Given
The radius of the circle = r = 5 in
We know that diameter is twice the radius.
so d = 2r = 2(5) = 10 in
<u>Finding the circumference of the circle in terms of pi</u>
Using the formula to find the circumference of the circle
C = dπ
C = 10×π
C = 10π inches
Thus, the circumference of the circle in term of pi = 10π inches
<u>Finding the circumference of the circle using π = 3.14</u>
We know that the formula to find the circumference of the circle
C = dπ
Given
π = 3.14
substituting π = 3.14 to find the circumference of the circle
C = 10×3.14
C = 31.4 inches
Thus, the circumference of the circle = 31.4 inches
Set up the equation
x = the smaller number
x + 15 = the larger number
x + x + 15 =39
solve for x
this will be the smaller number
add 15 to get the larger number
