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3 votes
I had to ask this again
Can someone help me please

I had to ask this again Can someone help me please-example-1
User Sehael
by
3.5k points

2 Answers

3 votes

Where the graphs of the functions intersect it represents the number of weeks when they have both saved the same amount of money. So by solving the system we can find the number of weeks and that amount of money.

y = x^2 + 2x

y = -3x + 6 so

x^2 + 2x = -3x + 6

x^2 + 5x - 6 = 0

(x + 6)(x - 1) = 0

So x = 1 ( we ignore the negative)

So after 1 week they have saved the same amount and the amount is -3 + 6 = 3.

Are you sure that -3x + 6 is right - because Sarah does not save anything after year 1 . The equation has a negative slope!!

User Gabe M
by
4.2k points
2 votes

Answer:

x=5

Explanation:

35+4x=x^2+30

collect the like terms n form a quadratic equation

x^2-4x-5=0

solve the quadratic equation

x=5 or x=-1

ignore the negative answer bcz week cant be negative

So the answer is 5 weeks

User Almo
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3.8k points