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)
The formula for the volume of a cone is V=(1/3)πr^2h.
To find r (radius) divide the diameter by 2, giving you 2.5 cm.
Plug in the numbers now !
V=(1/3)(3.14)(2.5^2)(9)
V=(1/3)(3.14)(6.25)(9)
V=(1/3)(176.625)
V=58.875
Therefore, the volume of the cone is about 59cm^3 :)
Answer:
44 square units
Step-by-step explanation:
The area of a trapezoid with bases b₁ and b₂ and height h is given by the formula
If you're wondering how we get this formula, check the attached illustration (remember the area of a parallelogram is its base multiplied by its height)! Moving on to our trapezoid, the pairs of points (-5,-3)(4,-3) and (6,-7)(-7,-7) form two horizontal segments, which form b₁ and b₂, and our height is the distance between the y-coordinates -3 and -7, which is 4. We can find b₁ and b₂ by finding the distance between the x coordinates in their pairs of points:
Putting it altogether:
So the area of our trapezoid is 44.
You'd likely find this problem easier if you'd write these two numbers on separate lines, one above the other:
1015
+119
-------
1134
Answer:
x = 15 degrees
3 angles in triangle are 44, 44 and 92 degrees.
Step-by-step explanation:
When the lines are parallel the internal angles add up to 180 degrees. So:-
8x + 7 + 2x + 23 = 180
10x + 30 = 180
10x = 150
x = 15
In the triangle:-
The angle adjacent to 136 = 180 - 136
= 44 degrees. As 2 sides of the triangle are congruent the other base angle = 44 degrees also.
The third angle = 180 - 2(44) = 92 degrees
