9514 1404 393
Answer:
18
Step-by-step explanation:
Solve the first for a, then substitute into the second.
a = 27/(5b^2)
Then ...
(27/(5b^2))^2·b = 135
27^2/(5^2·135) = b^3 = 27/125
b = ∛(27/125) = 3/5
a = 27/(5(3/5)^2) = 15
__
The expression of interest is ...
a +5b = 15 + 5(3/5) = 15 +3
a +5b = 18
Answer:
<em>C. 15</em>
Step-by-step explanation:
Assuming that these segments formed from each parallel line are proportional, x/5 = x-6/3.
Now cross multiply by multiplying each denominator by the opposite numerator, this is so the denominators or bottom numbers of each fraction will cancel.
x/5 = x–6/3 → (3)(x/5) = (3)(x–6/3) → 3x/5 = x–6 →
(5)(3x/5) = (5)(x–6) → 3x = 5(x–6) → 3x = 5x – 30.
The last step is to do the basic algebra to find x:
3x = 5x – 30
–5x –5x
[5x will cancel when you subtract both sides by 5x]
-2x = -30
(-1) (-1)
[2 negatives make a positive when -1 is multiplied by an expression with a negative coefficient]
2x = 30
÷2 ÷2
[divide both sides by 2 to simplify 2x to x]
x = 15
_____
You can also check that both sides are proportional because
5 → x
x = 15
5 → 15
3 → x – 6
x = 15
3 → 9
5 × <u>3</u> = 15
3 × <u>3</u> = 9
Use the velocity formula and solve for time.v=d/t
t=d/v
Substitute your variables and solve.
65 mi/hr = 65 / 3600 mi/second
25 mi / ( 65/3600) = 1384.6 seconds
Answer:
6x^2 + 4x
Step-by-step explanation:
g(x) + f(x)
= -8x^2 - 3x + 5 + 2x^2 + 7x - 5
= -8x^2 + 2x^2 - 3x + 7x + 5 - 5
= - 6x^2 + 4x
Answer:
x = 9
Step-by-step explanation:
Use the equation of the line, and let y = 0. Then solve for x.
y = 2/3 x - 6
Let y = 0:
0 = 2/3 x - 6
Add 6 to both sides.
6 = 2/3 x
Multiply both sides by 3/2.
3/2 * 6 = x
x = 9
