W is width
W+9 is length
W+W+9=54
2w=45
45/2
W=22.5
Width is 22.5 length is 31.5
The triangles are similar so the angles are equal
2x^2 - 2 = 10x - 2
2x^2 - 2 - 10x + 2 = 0
2x^2 - 10x = 0
2x(x - 5) = 0
2x = 0 OR x - 5 = 0
x = 0 OR x = 5
0 doesn't make sense, because IF I plug 0 into 2x^2 - 2 I get a negative number. We need to use 5 to find the angle measure
2(5^2) - 2 = 2(25) - 2 = 50 - 2 = 48 degrees or the measure of CED
12. 37, 370, 10^2
13. 20.4, 10^2, 2040
15. 1000*1.75=1750
Hope it helped!
Answer:
$0.37 and $0.31
Step-by-step explanation:
Answer: The area of the triangle ABC is 168 cm square.
Explanation:
Let the area of the triangle ABC be x cm square.
It is given that In △ABC point D is the midpoint of AB
, point E is the midpoint of BC
, and point F is the midpoint of BE
.
As we know that a median of a triangle divides the area of a triangle in two equal parts. Since D is a midpoint of AB and AD is median of triangle ABC. So area of triangle ACD and BCD is half of the area of triangle ABC.
The area of ACD and BCD is
.
Since E is a midpoint of BC and DE is median of triangle BCD. So area of triangle BDE and CDE is half of the area of triangle BCD.
The area of BDE and CDE is
.
Since F is a midpoint of BE and DF is median of triangle BDE. So area of triangle BDF and DEF is half of the area of triangle BDE.
The area of BDF and DEF is
. As shown in below figure.
It is given that the area of △DCF= 63 cm.
From the figure the area of △DCF is,




Therefore the area of triangle ABC is 168 cm square.