Answer:
a=6.9
Step-by-step explanation:
a(2)+4(2)=8(2)
4×4=16 8×8=64
16-16 64-16
a(2)=6.9
Caculator:
Press 2nd, press x2(close to bottom left)
6.92 PLEASE ROUND
6.92=6.9
a=6.9
All you've got to do is multiply both 13 and 20 by 5 so the fractions would be 65/100. Since you're trying to convert it into a decimal, you would move the decimal point 2 units to the right. This will result in the answer : 0.65.
Changing 13/20 would be 0.65
Given the equation:
cos²(x) + 9cos(x) = 5cos(x) + 5
cos²(x) + 9cos(x) - 5 cos(x) - 5 = 0
cos²(x) + 4cos(x) - 5 = 0
[cos(x) + 5][cos(x) - 1] = 0
cos (x) = - 5 x ∉ ℝ; so:
cos (x) = 1
Then;
x = 0, and x = 2π