18<span>,36,54,72,90,108,126,144,162,180,198,216,234,252,
hope this helps!</span>
Answer:
Step-by-step explanation:
We are to show that 
<u>Proof:</u>
From trigonometry identity;


From trigonometry, 2sinAcosA = Sin2A

Also note that sin(B-C) = sinBcosC - cosBsinC
sin420cos140 - cos420sin140 = sin(420-140)
The resulting equation becomes;

= 
Answer: 1080 
Determine the values of b1, b2, and b3, the sides of the triangular base. Also determine the value of h, the height of the triangular base and l, the length of the prism (the length between the bases).
The sides of the triangular base are:
b1 = 13 in.
b2 = 14 in.
b3 = 15 in.
The triangular base is a right triangle, and so the height is one of our sides. We will use
h = 12 in.
The length of the prism is
l = 20 in.
total surface area = bh + (b1+b2+b3)*l
bh = 12*20 = 240 
l * (b1+b2+b3) = 20*(13 + 14+ 15) = 840 
TSA = bh + l * (b1 + b2 + b3) = 240 + 840 = 1080 
to know more about prism,
brainly.com/question/16128664
Answer:
(x, x2 − 3x − 28) for all real numbers
Step-by-step explanation: