Step-by-step explanation:
L.H.S=(1-cosB)(1+cosB)
=(1-cos^2B). {using (a+b) (a-b)=(a^2-b^2)in second step}
=sin^2B
=1/cosec^2B
Therefore,L.H.S=R.H.S proved
The answer is 1 Bcuz u have to first plug in -4 for f then solve the equation by adding like terms and dividing
Answer:
Subtract 2x to bring it to the other side
Step-by-step explanation:
2x+5y=20
-2x. -2x
5y=-2x+20
Answer:
A. 25 B. 45 C. 30
Step-by-step explanation:
A.
75 ÷ 3 = 25
25 × 1 = 25
B.
75 ÷ 5 = 15
15 × 3 = 45
C.
50 ÷ 5 = 10
10 × 3 = 30
Answer:
Step-by-step explanation:
AB^2 = HB^2 + AH^2 => AB = 15cm
Ta co cong thuc: 1/AH^2 = 1/AB^2 + 1/AC^2 => AC=20cm
Vay SABC= 1/2 .AB.AC = 1/2 .15.20=150cm^2