Answer:
Step-by-step explanation:
4. 10x + 30 = 90
10x = 60
x = 6
complementary
5. 4x + 40 + 3x = 180
7x + 40 = 180
7x = 140
x = 20
supplementary
Answer:
y = 460 miles per hr
x = 500 miles per hr
Step-by-step explanation:
Let the planes be X any
Let their speeds be xmiles/hr and ymiles/hr respectively
x = y + 40 (assuming X is faster by 40miles/hr)
Distance travelled by X to meet Y = 0.75x
Distance travelled by Y to meet X = 0.75y
0.75x + 0.75y = 720 --------1
Put x = y + 40 in eqn 1
0.75(y+40) + 0.75y = 720
0.75y + 30 + 0.75y= 720
1.5y = 690
y = 460 miles per hr
x = 460 +40
= 500 miles per hr
<h2>
Hello!</h2>
The answer is:
B. 
<h2>
Why?</h2>
From the statement we know that the cheetah can reach a speed of 70 mph, but it can be maintained for no more than 1,640 feet.
The expression "no more than" means that at least it can be reached but never exceeded, it involves that the distance can be less or equal than 1,640 feet but never more than that.
So, the correct option is:
B. 
Have a nice day!