Answer:
Step-by-step explanation:
hello :
cos²θ +sin²θ = 1 and cosθ =4/5
(4/5)² + sin²θ = 1 so : sin²θ = 1 - 16/25
sin²θ = 9/25 = (3/5)²
sinθ = 3/5 or sinθ = - 3/5 because : (3/5)²= (- 3/5)²= 9/25
Step-by-step explanation:
Divide 180 by 3 = 60
Divide 150 by 2 = 75
The faster vehicle is truck and its speed is 75 mph
Area = length *width
A = x²
3x² = (x+10)(x+12)
3x² = x²+10x+12x+120
3x² = x²+22x+120
3x²-3x² = x²+22x+120-3x²
0 = -2x²+22x+120
Factor to solve for x:
-2(x²-11x-60)
(x+4)(x-15)
x = -4 & x = 15 but we can't have a negative length so we eliminate 4. The length of the square is 15 cm.
You could multiply 19.45 by 0.2 to solve for it, but if you're not using a calculator, then 19.45/5 would be much more convenient and easier.
0.2 is 1/5 in fraction form, which is why we can do that.
19.45/5 = 3.89
Dino should leave $3.89 as a tip.
