What is the rectangle's height and base?

base = 16 cm

height = 7 cm

Step-by-step explanation:

area of a rectangle = base (b) x height (h)

base (b) = 9 + h

area = 112 cm²

plug in values:

112 = (9 + h) * h

112 = 9h + h²

h² + 9h - 112 = 0

h can be solved using quadratic equation

       -9 ± √ (9² - 4 (1) (-112))

h =

                        2

     -9 ± √529

h =

            2

h = 7  ;    h = -16

therefore  the height of  a rectangle (h) = 7 cm

solve for base (b)

base (b) = 9 + h

base (b) = 9 + 7

base (b) = 16 cm

proof:

area of a rectangle = base (b) x height (h)

112 = 16 * 7

112 = 112 ok

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places