Answer:
A = 40°
B = 50°
Step-by-step explanation:
If cos A = sin B, then A + B = 90
So, 2x/3 + 20 + 2x - 10 = 90
2x + 60 + 6x - 30 = 270
8x + 30 = 270
8x = 240
x = 30
2x/3 + 20 = 60/3 + 20 = 20 + 20 = 40
2x - 10 = 2(30) - 10 = 60 - 10 = 50 or 90 - 40 = 50
Answer:
16.5
Step-by-step explanation:
this is very true because it is
we know there are 5280 feet in 1 mile, and there are 3600 seconds in 1 hour.
Answer:
False; they are equal.
Step-by-step explanation:
The equation is x + 20 > 4x - 1.
First, do the opposite of -1 and add one to the other side while -1+1 cancels out. Now it's x+21 > 4x. Now subtract x from both sides. Positive x minus negative x cancels out and 4x minus x or 1x is 3x. Now you're left with 21> 3x. Now do the inverse operation of multiplication and divide both sides by 3. Now the 3x over 3 cancels out and 21 divided by 3 is 7. So x is 7. If you substitute it in. It will be 7+20 which is 27 which is great than 4(7)-1 which is 28-1. 28-1 is 27. So, the equation is false. They are equal.
Answer:
The formula to calculate standard deviation from probability is \sqrt(n*p*(1-p)). n is the sample size, and 200 in this case (number of putts for practice). p is 80% or 0.8, the probability that he can make it. So the standard deviation is \sqrt(200*0.8*(1-0.8)=\sqrt(200*0.8*0.2)=\sqrt(16)=4.