Respuesta :

Answer:

a = [tex]\frac{1}{2}[/tex] , b = 5, and  [tex]\frac{2b}{a}[/tex] = 20

Step-by-step explanation:

f(x) = - x² + b, x ≤ 0     You would use this equation for f(-2). Since -2 is less than 0.

f(x) = - x² + b, x ≤ 0   ← You can ignore the x ≤ 0 part.

f(-2) = - (-2)² + b         Input the value -2 as x. The question states that f(-2) =1.

1 = - (-2)² + b              So switch f(-2) with 1 on the left side only.

1 = - (4) + b                Simplify. Do the exponents first, so (-2)² = 4.

1 = - 4 + b

+4  +4                      Do inverse operations

5 = b

Next,

f(x) = 2ax +3, x > 0      You would use his equation for f(2). Since 2 is greater than 0.

f(x) = 2ax +3, x > 0   ← You can ignore the x > 0 part.

f(2) = 2a(2) + 3             Input the value 2 as x.

f(2) = 4a +3           Simplify. The equation states f(2) = 5. So switch f(2) with 5

5 = 4a +3              on the left side only.

-3        - 3                     Do inverse operations

2 = 4a                          

[tex]\frac{2}{4}[/tex] = [tex]\frac{4a}{4}[/tex]                           Divide 4 on both sides to isolate the variable a

[tex]\frac{2}{4}[/tex] = a                            Simplify

[tex]\frac{1}{2}[/tex] = a

Then,

The second part says to find [tex]\frac{2b}{a}[/tex]

[tex]\frac{2b}{a}[/tex]

[tex]\frac{2(5)}{(\frac{1}{2}) }[/tex]                  Input both the values of a and b

[tex]\frac{10}{\frac{1}{2} }[/tex]                    Simplify

20.

The answer for a is [tex]\frac{1}{2}[/tex], the answer for b is 5, and the answer for [tex]\frac{2b}{a}[/tex] is 20.