Answer:
(3x+4)(5x+7)
Step-by-step explanation:
15x^2
+41x+28
Factor the expression by grouping. First, the expression needs to be rewritten as 15x^2
+ax+bx+28. To find a and b, set up a system to be solved.
a+b=41
ab=15×28=420
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 420.
1,420
2,210
3,140
4,105
5,84
6,70
7,60
10,42
12,35
14,30
15,28
20,21
Calculate the sum for each pair.
1+420=421
2+210=212
3+140=143
4+105=109
5+84=89
6+70=76
7+60=67
10+42=52
12+35=47
14+30=44
15+28=43
20+21=41
The solution is the pair that gives sum 41.
a=20
b=21
Rewrite 15x^2
+41x+28 as (15x^2
+20x)+(21x+28).
(15x^2
+20x)+(21x+28)
Factor out 5x in the first and 7 in the second group.
5x(3x+4)+7(3x+4)
Factor out common term 3x+4 by using distributive property.
(3x+4)(5x+7)
For the second question, your first option is correct, you would rewrite 8 in power-base form 8=2^3 as the first step to solving the equation, power base form is exponential form.
Answer:
-6d - (c - d)^2 = -33
Step-by-step explanation:
-6(4) - (3)^2 =
-24 - 9 =
-33
Answer:
94.2 cm
62.8 inch
Step-by-step explanation:
The circumference of a circle is 2πr, where r is the radius.
The diamater is twice the radius, d=2r.
1) 2π·15 ≈ 94.2 cm
2) r = 10 inch. 2π·10 = 62.8 inch.
$0.09 per ounce Because there are 16 ounces in a pound, 3.4 pounds is 3.4(16) = 54.4 ounces. To find cost per ounce, divide the cost in dollars by the number of ounces
