Answer:
-2x³ + x² - 3x - 15
Step-by-step explanation:
Simply combine like terms together:
-5x² - 3x - 7 - 2x³ + 6x² - 8
-2x³ + (-5x² + 6x²) - 3x + (-7 - 8)
-2x³ + x² - 3x + (-7 - 8)
-2x³ + x² - 3x - 15
Here’s your answer. Hope this helped!!
Answer:
x = 5
y = 11
Step-by-step explanation:
y = 4x - 9
2x -3(4x - 9) = -23
2x - 12x + 27 = -23
-10x = -23 -27
-10x = -50
minus cancels out
x = 5
y = 4(5) -9
y = 20 - 9
y = 11
Answer: 2343 / 256
Explanation
I will do this for you in two forms: 1) adding each term, and 2) using the general formula for the sum of geometric series.
1) Adding the terms:
4
∑ 3 (3/4)^i = 3 (3/4)^0 + 3 (3/4)^1 + 3 (3/4)^2 + 3 (3/4)^3 + 3 (3/4)^4
i=0
= 3 + 9/4 + 27/16 + 81/64 + 243/256 = [256*3 + 27*16 + 64*9 + 4*81 + 243] / 256 =
= 2343 / 256
2) Using the formula:
n-1
∑ A (r^i) = A [1 - r^(n) ] / [ 1 - r]
i=0
Here n - 1 = 4 => n = 5
r = 3/4
A = 3
Therefore the sum is 3 [ 1 - (3/4)^5 ] / [ 1 - (3/4) ] =
= 3 [ 1 - (3^5) / (4^5) ] / [ 1/4 ] = 3 { [ (4^5) - (3^5) ] / (4^5) } / {1/4} =
= (3 * 781) / (4^5) / (1/4) = 3 * 781 / (4^4) = 2343 / 256
So, no doubt, the answer is 2343 / 256
1 and half hour
= 60 minutes+ 30 minutes
= 90 minutes
Now,
Uzanne need 15 minutes to do 10 problems
Uzanne need 1 minute to complete 10/15 problems
Uzanne need 90 minutes to do
= (10/15)*90
=(2/3)*90
=2*30
=60 problems