ANSWER
B. The two middle coefficients add to the correct number but do not multiply to the correct number.
EXPLANATION
The given quadratic trinomial that Tina tries to factor is

Comparing to

we have a=10, b=-13 and c=-3
ac=-3×10=-30
We split the middle term so that their sum is -13.
Tina use
-10,-3
to get
-10x-3x
The sum is -13x alright but the product is not -30.
B is correct.
Monthly salary of Kedar = $2000
Percentage commission on the amount of his sales = 3.75%
Amount of money for which clothing sold by Kedar = $4500
Amount of interest earned by Kedar this month = (3.75/100) * 4500
= 3.75 * 45
= 168.75 dollars
So
The total amount earned by Kedar this month = (2200 + 168.75) dollars
= 2368.75 dollars
So Kedar earned a total amount of $2368.75 this month.I hope the procedure is absolutely clear to you.
549 ÷ 67 = 8.194029851
Hope this helps :)
Answer:
A) -84x^3 - 8x
B) -91x^4 + 143x^2 - 65x
C) 12b^2 - 7b - 10.
D) 16x^2 - 72x + 81
Step-by-step explanation:
A) -4x(21x^2-3x+2)
B) -13x(7x^3-11x+5)
C) (3b+2)(4b-5)
D) (4x-9)^2
In A) -4x(21x^2-3x+2) we are multiplying the binomial (21x^2-3x+2) by the monomial -4x; there are two multiplications involved:
-4x(21x^2) = -84x^3
and
-4x(-3x+2) = +12x^2 - 8x.
Hence A) -4x(21x^2-3x+2) = -84x^3 - 8x
B) The work done to find the product in B) is similar: Multiply each term in 7x^3-11x+5 by -13x:
The end result is -91x^4 + 143x^2 - 65x
C) Here we are multiplying together two binomials; we use the FOIL method: Multiply together the First terms, then the Outer terms, then the Inner terms, and finally the Last terms. This results in:
(3b+2)(4b-5) = 12b^2 -15b + 8b -10, or, after simplification, 12b^2 - 7b - 10.
In D) we are squaring a binomial. The formula for this is:
(a - b)^2 = a^2 - 2ab + b^2. Here,
(4x - 9)^2 = 16x^2 - 2(36x) + 81, or 16x^2 - 72x + 81