Answer:
The missing length would be 24.
First, you find the ratio of 55 to 33.
This gets you approximately 1.66666667
Multiply 36 by 1.66666667. This will get you 60.
60 - 36 = 24
The unknown value is 24.
You could simplify this work by factoring "3" out of all four terms, as follows:
3(x^2 + 2x - 3) =3(0) = 0
Hold the 3 for later re-insertion. Focus on "completing the square" of x^2 + 2x - 3.
1. Take the coefficient (2) of x and halve it: 2 divided by 2 is 1
2. Square this result: 1^2 = 1
3. Add this result (1) to x^2 + 2x, holding the "-3" for later:
x^2 +2x
4 Subtract (1) from x^2 + 2x + 1: x^2 + 2x + 1 -3 -1 = 0,
or x^2 + 2x + 1 - 4 = 0
5. Simplify, remembering that x^2 + 2x + 1 is a perfect square:
(x+1)^2 - 4 = 0
We have "completed the square." We can stop here. or, we could solve for x: one way would be to factor the left side:
[(x+1)-2][(x+1)+2]=0 The solutions would then be:
x+1-2=0=> x-1=0, or x=1, and
x+1 +2 = 0 => x+3=0, or x=-3. (you were not asked to do this).
Answer:
-2.8
Step-by-step explanation:
Given that:
Mean, μ = 78
Standard deviation, σ = 5
Omar's score, x = 64
The Zscore of Omar's score :
Zscore = (x - μ) ÷ σ
Zscore = (64 - 78) / 5
Zscore = - 14 / 5
Zscore = - 2.8
Hence, Omar's exam score is - 2.8
