Charlie threw a ball up in the air modeled by the function f(x)=−x2+2x+4. Elizabeth release a balloon at the same time, represented by g(x)=2x. At what time do the paths cross and at what height?

Step-by-step explanation:

The paths crossed at when the height are equal i.e when f(x) = g(x)

Given

f(x)=−x^2+2x+4

g(x) = 2x

IF f(x) = g(x), then;

−x^2+2x+4 = 2x

−x^2+2x+4 - 2x = 0

−x^2+4 = 0

-x^2 = -4

x^2 = 4

x = ±√4

x = 2 and -2

Time cannot be negative

Hence x = 2

The path crossed after 2 seconds

rick has $1400 and sally has $1500

step-by-step explanation:

to find amount of money rick has after 10 years :

principal = $1000 , time = 10 years , rate = 4% annually

to find amount of money sally has after 10 years :

her friend gives to pay her $50 per year, therefore money she has after 10 years = 50 × 10 = $500

also, sally gets $1000 after 10 years,

therefore, total amount of money sally has after 10 years = 500 + 1000 = $1500

so, after 10 years : rick has $1400 and sally has $1500

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step-by-step explanation: