This is the working of how it is 28% discount
Find the amount of discount : $125 - $90 = $35
Divide by the original price : $35/125 = 0.28
Change in to percentage : 0.28 x 100 = 28%
Therefore the percentage discount is 28% off
:)
-1 > -2(x-4) - 5(4x - 7)
-1 > -2x + 8 - 20x + 35
-1 > -22x + 43
-1 - 43 > - 22x
-44 > - 22x
-44/-22 < x
2 < x....or x > 2
First translate the English phrase "Four times the sum of a number and 15 is at least 120" into a mathematical inequality.
"Four times..." means we're multiplying something by 4.
"... the sum of a number and 15..." means we're adding an unknown and 15 and then multiplying the result by 4.
"... is at least 120" means when we substitute the unknown for a value, in order for that value to be in the solution set, it can only be less than or equal to 120.
So, the resulting inequality is 4(x + 15) ≤ 120.
Simplify the inequality.
4(x + 15) ≤ 120
4x + 60 ≤ 120 <-- Using the distributive property
4x ≤ 60 <-- Subtract both sides by 60
x ≤ 15 <-- Divide both sides by 4
Now that we have the inequality in a simplified form, we can easily see that in order to be in the solution set, the variable x can be no bigger than 15.
In interval notation it would look something like this:
[15, ∞)
In set builder notation it would look something like this:
{x | x ∈ R, x ≤ 15}
It is read as "the set of all x, such that x is a member of the real numbers and x is less than or equal to 15".
ANSWER : (9u - 8)2
STEPS:
Step-1 : Multiply the coefficient of the first term by the constant 81 • 64 = 5184
Step-2 : Find two factors of 5184 whose sum equals the coefficient of the middle term, which is -144 .
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -72 and -72
81u2 - 72u - 72u - 64
Step-4 : Add up the first 2 terms, pulling out like factors :
9u • (9u-8)
Step-5 : Add up the four terms of step 4 :
(9u-8) • (9u-8)
Which is the desired factorization
