Answer:
Step-by-step explanation:
(a + b)² =a² + 2ab + b²
(a -b)² = a² - 2ab + b²
1) y = (x -1)²
y= x² - 2*x*1 + 1
y = x² - 2x + 1
Ans: C
2)y = (x +4)² + 5
y = x² +2*x*4 + 4² + 5
= x² + 8x + 16 + 5
y = x² + 8x + 21
C
3) y = -(x + 9)²- 10
y = - [x² + 18x + 81] - 10
= -x² - 18x - 81 - 10
y =-x² - 18x - 91
B
4) y = 3(x + 2)² - 18
y =3 [x² + 4x + 4] - 18
y = 3x² + 12x + 12 - 18
y =3x² + 12x - 6
A
5) y = -2(x + 1)² - 16
= -2[x² + 2x + 1] -16
= -2x² - 4x - 2 - 16
y = -2x² - 4x - 18
A
6) y = 5(x + 5)²
=5[x²+ 10x + 25]
y = 5x² +50x + 125
A
7)y = (1/2)(x + 8)² - 8
y = (1/2) (x² + 16x + 64) - 8
A
8) y = (x + 3/2)² + 3/4
C
9) y = 2[x² + 16x + 64] - 5x
y = 2x² + 32x + 64 - 5x
y =2x² + 27x + 6
Answer:
104
Step-by-step explanation:
260x.4=104
The value of x is 5.5. I got this answer by first distributing -3 amongst (x-11), and distributing 7 amongst (2x-5). Next I combined like terms and subtracted 3x from 5x, and added -35 and 2. Next I subtracted 33 from both sides. Next I subtracted 14x from both sides. And finally I divided both sides by -12 to get the final answer of 5.5.
Hi there!
Recall the formula:
Δd = vt, where:
v = velocity (mph in this instance)
t = time (hours)
Since the second car starts 2 hours after the first car, we can write this as:
Time for second car: t - 2
Set the two equations equal to each other:
55(t - 2) = 45t
Solve for t:
55(t - 2) = 45t
Simplify:
55t - 110 = 45t
10t = 110
t = 11 hours
Plug into one of the equations:
distance travelled = 45(11) = 495 miles
Use the substitution method:
2x - 6y = -12
x - 2y = -8
Then x = 2y - 8
Substitute in the first equation:
2(2y - 8) - 6y = -12
4y - 16 - 6y = -12
-2y = 4
y = -2
Now substitute y in one of the two equations given you prefer:
For example x-2*(-2) = -8
x + 4 = -8
x = -12
The solutions are x = -12 and y = -2