x = number of questions
3y = points for a correct answer
-1x or -x = points for an incorrect answer
Adding up the correct and incorrect points/answers gives us the final score. We can solve to see how many questions were incorrect. (We are told 10 were correct)
3y + (-1x) = 20
3(10) + (-1x) = 20
30 - x = 20
10 = x
x = 10
So she got 10 correct and 10 incorrect, and there were 20 questions in all.
Answer:
30°
Step-by-step explanation:
It tells us that MFE is equal to (x + 6)° so we need to find x
The angle accross from MFE is RFT. These angles are congruent, because they are a vertical pair. So RFT is also equal to (x + 6)°
The angle RFT and PFR combined form a right angle. This means that RFT + PFR = 90°.
They told us that PFR = (3x - 4)°
so that means that (x + 6) + (3x - 4) = 90°
Knowing that we can just solve the equation by combining like terms
4x + 2 = 90
Subtract two from both sides
4x = 88
And then divide by 4
x = 22
Now we can plug in 22 in the original equation to find MFE
22 + 6 = 30
so MFE = 30°
Answer:
Step-by-step explanation:
4⅖ = 22/5 = 242/55
-3 2/11 = -35/11 = -175/55
k = -175/55 - 242/55 = -417/55 = -7 32/55
6x²-5x-4=0
x=(-b+/√b²-4ac)/2a
D=b²-4ac=25+4*6*4=121, √D=√121=11
x=(5+/-11)/12
x1=-6/12=-1/2
x2=16/12=4/3
Answer:
The equation for difference in altitude of the two helicopters is A = 650 - 100t
Step-by-step explanation:
Given;
The altitude of one helicopter is, A1 = 600 + 150t
The altitude of a second helicopter is, A2 = 1250 + 50t
Their difference in altitude, A at time t, is calculated as
A₂ - A₁ = A = (1250 + 50t) - (600 + 150t)
A₂ - A₁ = A = 1250 + 50t - 600 -150t
A₂ - A₁ = A = 1250 - 600 + 50t - 150t
A₂ - A₁ = A = 650 - 100t
Therefore, the equation for difference in altitude of the two helicopters is A = 650 - 100t