Answer:
The player answer correctly 30 questions
Step-by-step explanation:
First we have to develop the information that gives us as 2 equations
x = correct answer
y = incorrect answer
z = score = 40
h = total answer = 50
2x - y = z x + y = h
2x - y = 40 x + y = 50
we clear the x of one equation and replace the value of x in the other equation
x = 50 - y
2x - y = 40
2(50 - y) - y = 40
100 - 2y - y = 40
-3y = 40 -100
y = -60/-3
y = 20
x = 50 - y
x = 50 - 20
x = 30
Answer:
12 beats per minute after 30minutes
Step-by-step explanation:
Since we are told by how much his heartrate increased in 20 minutes, we can simply calculate how much it increased in 10 minutes and add that amount to the current heart rate to know how much his heartrate increased after 30 minutes of working out. Since 10minutes would be half of the 20minutes we simply divide the beats per minute by 2.
8 / 2 = 4 beats per minute after 10 minutes
Now we simply add this to the beats per minute at the 20minute mark to calculate the beats per minute at 30minutes
8 + 4 = 12 beats per minute after 30minutes
(a - 2b) • (2a - b) is how you factor this using FOIL
Divide both sides by by
su/vt =r
Is there more to the question? Because it could be any hours..
