20%*x = 8
20% = 2/10
2/10*x = 8 |(*10/2)
2/10*10/2*x= 8 * 10/2 2/10*10/2 =>1
1*x = 80/2
x=40
25% from 40 is 10
25% = 1/4
1/4 * 40 = 40/4 = 10
Reflection over the y-axis is like a mirror image across the vertical axis. It is equidistant from the y axis on the other side and the x coordinate stays the same.
So, your new point is the fourth choice, (4, -2).
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.
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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:
3
Step-by-step explanation:
1+2x=7
7-1=6
2x=6
6/2=3
x=3
Answer:
-15
Step-by-step explanation:
-3 + -12 = -15
