So we know that an average is the sum of the scores divided by the number of scores that were added together. In this case we are going to be dealing with 4 tests. So let's say x is the score for our fourth test. We can create this equation:
So then we need to simplify the top:
Then multiply by 4 on both sides to get rid of the denominator:
Then solve for x:
So now we know that Sam needs to score a 67 on the fourth test to have an average score of 50.
Answer:
n= 1/2 ( ) or (0.5)
AND
n= -3/2 ( ) or (-1.5)
Step-by-step explanation:
4n^2+4n=3
step1: move 3 to the other side and make the equation equal to zero.
4n^2+4n-3=0
step2: factorise the equation.
(2n-1)(2n+3)=0
step3: make each bracket equal to zero.
2n-1=0
2n+3=0
step4: solve for n values.
<u>1.</u> 2n-1=0
(add 1 for both sides)
2n=1
(divide by 2 for both sides)
n= 1/2 ( ) or (0.5)
<u>2.</u> 2n+3=0
( subtract 3 for both sides)
2n=-3
(divide by 2 for both sides)
n= -3/2 ( ) or (-1.5)
Answer:
A) x=5 or -11
Step-by-step explanation:
The given equation is:
The most suitable method so solve this quadratic equation is the square root method.
We take square root of both sides to obtain:
We now split the plus or minus sign to get;
This simplifies to:
The correct choice is A