Answer:
- C) (x − 3)2 = 25
- C) Factor out 4 from 4x2 + 40x.
Step-by-step explanation:
1. Adding the square of half the x-coefficient to both sides of the equation will "complete the square." That square is 9, so the result on the right is 16+9 = 25. Only selection C matches.
___
2. To complete the square, you want to be able to put the quadratic into the form a(x -h)^2 = -k. For the purpose, it is most convenient to first factor "a" from the given quadratic. Then you can determine "-h" to be half the x-coefficient inside the parentheses.
Here, that looks like ...
4(x² +10x) = 80 . . . . . . . . . . step 1: factor out 4
4(x² +10x +25) = 180 . . . . . add 25 inside parentheses and the same number (4·25) on the right side of the equation
4(x +5)² = 180 . . . . . . . . . . . written as a square
Answer:
x = 3
Step-by-step explanation:
These angles are actually equal to each other
This is because when two lines intersect, the two opposite angles are the same.
Since they are the same, you can set them equal to each other
Like so:
6x - 7 = 4x - 1
Then solve:
6x - 7 = 4x - 1
6x = 4x +6
2x = 6
x = 3
<span>Given the diagram, where AB and EF are horizontal lines and CB is a vertical line segment.
Given that FB : FC = 4 : 3,
From the diagram, the coordinate of A is (-10, -8) and the coordinate of C is (-3. -1).
We can also see that the coordinate of B is (-3, -8) (since CB is a vertical line means that B is the same x-value as C and AB is a horizontal line means that B is the same y-value as A)
Recall that the coordinate of a point dividing a line segment in the ratio m:n is given by (x1 + m/(m+n) (x2 - x1), y1 + m/(m+n) (y2 - y1))
Thus, since FB : FC = 4 : 3, this means that point F divides the line segment BC in the ratio 4 : 3.
Thus, the coordinate of F is given by (-3 + 4/(4+3) (-3 - (-3)), -8 + 4/(4+3) (-1 - (-8))) = (-3 + 4/7 (0), -8 + 4/7 (7)) = (-3, -4).
Also, given that FB : FC = 4 : 3, this means that point D divides the line segment AC in the ratio 4 : 3.
Thus, the coordinate of D is given by (-10 + 4/(4+3) (-3 - (-10)), -8 + 4/(4+3) (-1 - (-8))) = (-10 + 4/7 (7), -8 + 4/7 (7)) = (-6, -4).
Therefore, the coordinates of point D is (-6, -4).</span>
