Writing Equations From Graphs...4

[nycmathguy]

Section 1.7
Question 50

See attachment.

50a. The general form is y = a•sqrt{x}.

Use the given point to find a.

16 = a•sqrt{4}

16 = 2a

16/2 = a

8 = a

f(x) = 8•sqrt{x}.

50b.

The general form is y = a•sqrt{x}.

Use the given point to find a.

-1/2 = a•sqrt{4}

-1/2 = 2a

(-1/2)/2 = a

1/4 = a

f(x) = (1/4)sqrt{x}.

 

[MathLover1]

correction to this part

(-1/2)/2 = a -> you are dividing negative number (-1/2) by positive number 2, so quotient will be negative number

-1/4 = a
f(x) = -(1/4)sqrt{x}.

 

[nycmathguy]

correction to this part

(-1/2)/2 = a -> you are dividing negative number (-1/2) by positive number 2, so quotient will be negative number

-1/4 = a
f(x) = -(1/4)sqrt{x}.

It was a typo at my end. Negative ÷ Positive = Negative.