Answer:
C. (3x2 - 10) (x - 2)
Step-by-step explanation:
3x^2 - 16x +20
Step 1: Sum = - 16x
Product = 60x^2
Step 2: Find 2 numbers that their sum is -16 and their product is 60. If you do that correctly, then you will get two numbers: 10 and -6
Step 3: Replace -16x with the two numbers found in step 2, then you will have; 3x^2 - 6x - 10x + 20
Step 4: Factorise the equation in step 3, like so;
(3x^2 - 6x)(- 10x + 20)
3x(x - 2) -10(x - 2)
(3x - 10)(x - 2)
To check if the answer is correct, expand the bracket: (3x - 10)(x - 2)
If the bracket is opened properly, you will get 3x^2 - 16x + 20
Answer:
Restate the question
Step-by-step explanation:
direct proportion y=kx , k is constant and k does not equal to 0.
17.5=k(21)
k=5/6
when x =39
y=5/6 ×39
y=32.5
Let
x ----------> the height of the whole poster
<span>y ----------> the </span>width<span> of the whole poster
</span>
We need
to minimize the area A=x*y
we know that
(x-4)*(y-2)=722
(y-2)=722/(x-4)
(y)=[722/(x-4)]+2
so
A(x)=x*y--------->A(x)=x*{[722/(x-4)]+2}
Need to minimize this function over x > 4
find the derivative------> A1 (x)
A1(x)=2*[8x²-8x-1428]/[(x-4)²]
for A1(x)=0
8x²-8x-1428=0
using a graph tool
gives x=13.87 in
(y)=[722/(x-4)]+2
y=[2x+714]/[x-4]-----> y=[2*13.87+714]/[13.87-4]-----> y=75.15 in
the answer is
<span>the dimensions of the poster will be
</span>the height of the whole poster is 13.87 in
the width of the whole poster is 75.15 in
P-0.40p = 0.60p
C. Decrease by 40% is the same as multiply by 60%.
Assume that p = 10
10 - 0.40(10) = 0.60(10)
10 - 4 = 6
6 = 6
Based on the above assumption. 40% of 10 is 4 ; and 60% of 10 is 6. So, 10 less 4(40% of 10) is equal to 6 (60% of 10).
Percentage is used because 0.40 and 0.60 will be multiplied with 100% to get the equivalent percentage 0.40 x 100% = 40% ; 0.60 x 100% = 60%
