Answer: 25x² - 64
<u>Step-by-step explanation:</u>
(5x + 8)(5x - 8)
= 5x(5x - 8) + 8(5x - 8)
= 25x² - 40x + 40x - 64
= 25x² + 0x - 64
= 
NOTE: descending powers means the biggest exponent goes first, then the next biggest exponent, etc.
For example: x⁴ then x³ then x² then x then the number (which is actually x⁰)
Answer:
The value of x is 3.
Step-by-step explanation:
Matthew earned 7500 of 15000, which is exactly half the total amount, meaning that the fraction corresponding to his earnings is 1/2.
Rate of 5:2:x, with number 5 corresponding to Matthew, mean that his fraction of the earnings, in function of x is given by:

Both fractions are equal, so:

Applying cross multiplication:



The value of x is 3.
1.3*3=3.90
3.90*35=136.50
136.50 is all you need to provide at least three of the most expensive items.
You still have 13.50 left over
1. Reduce <span>3x2-6x-240 to x^2 - 2x - 80
2. Use " ^ " to indicate exponentiation
3. Factor </span>x^2 - 2x - 80 using completing the square:
x^2 - 2x + 1^2 - 1^2 - 80
(x+1)^2 - 1 - 80
(x+1)^2 - 81
(x+1)^2 - 9^2 = (x+1-9)(x+1 +9), or (x-8)(x+10)
Final answer, with all factors shown: 3(x-8)(x+10)
Answer:
The solution of the equation 4x+y=5 and 3x+y=3 be (2 , -3) .
Option (D) is correct .
Step-by-step explanation:
As given the equations are .
4x+y=5
3x+y=3
Subtracted 3x+y=3 from 4x+y=5 .
Thus
4x - 3x + y - y = 5 - 3
x = 2
Put in the equation 4x+y=5 .
4 × 2 + y = 5
8 + y = 5
y = -8 + 5
y = -3
Therefore the solution of the equation 4x+y=5 and 3x+y=3 be (2 , -3) .
Option (D) is correct .