Answer:
see explanation
Step-by-step explanation:
Using the identities
sin(A + B) = sinAcosB + cosAsinB
cotA = 
, tanA = 
Consider the left side
= 
= 
+ 
= 1 + . 
= 1 + cotA tanB = right side , thus verified
1720 - 1040 = 680
680/7 = 97.1
I would put them in intervals of 100
A is the correct answer. I have already done this and got A and it was right. I hope it is the same to yours. :D
I hope this helped!
Given that Macy wants to construct an isosceles triangle, with the unique angle being 40° it implies that for the triangle to be isosceles, the base angles should be the same. The size of the base angles will be:
(180-40)/2=70
given that that the base is 6 cm, Macy can only form 1 triangle with these dimensions.
The length of the other sides will be found using sine rule
a/sin A=b/sin B
a=6 cm
A=40°
b=?
B=70
hence:
6/sin 40=b/sin 70
b=(6sin 70)/sin40
b=8.77 cm
The formula for area of a trapezoid is:
Sides a is the top line and side b is the base, or bottom line. Add the sides together and divide by 2. After you do that, multiply the answer by the height.
Height is the length between the two sides, a and b.
