Answer:
-2
Step-by-step explanation:
If we have an equation of the form y = mx +b then the y-intercept is b.
So now here we have y =-x - 2. Therefore b = -2 and we conclude the y-intercept is -2.
Answer:Mark Is 9 years old; Christine is 5 years old
Step-by-step explanation:
Present age
LET mark age be x
Christine be x-4 yrs
In 3 yrs Time
Mark will be x+3 yrs old
Christine will be (x -4 +3) = x-1 years old
Also, In 3 years time
Christine = 2/3 Mark
such that
x-1 = 2/3(x+3)
x -1= 2x+6 / 3
3x -3= 2x+6
3X--2X = 6+3
=X=9
Mark Is 9 years old
Christine is x -4 = 9-4=5 years old
Ben's estimate gives 7 g of nickel; the actual amount is 8.03 g.
In 1 g of the substance, there is 0.52 g of copper and 0.25 g of zinc; this gives
0.52+0.25 = 0.77 g of the substance.
The remaining part of the substance is nickel:
1-0.77 = 0.23 g of nickel.
Using Ben's estimate, 0.2 g of nickel per gram of substance, we have
0.2(35) = 7 g of nickel in 35 g of the substance.
The actual amount is 0.23(35) = 8.03 g of nickel in 35 g of the substance.
The Z-score is calculated by the formula below
Step 2: Substitute the given parameters in the formula
Hence, the z-score of a person who scored 145 on the exam is -0.5
