X + y = 3
2x + 4y = 8
This is a system of equations. You can solve it using elimination. Start by multiplying the top equation by -2.
(x * -2) + (y * -2) = (3 * -2)
-2x - 2y = -6
Now add that and the bottom equation. This will cancel out x.
-2x - 2y = -6
+ 2x + 4y = 8
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2y = 2
Solve for y.
2y = 2
y = 2/2
y = 1
Now plug 1 in for y in the first equation.
x + y = 3
x + 1 = 3
Solve for x.
x + 1 = 3
x = 3 - 1
x = 2
So x = 2 and y = 1.
So your equation is y = x² - 20x + 15. what you'll want to do is complete the square, so take half of 20 and square it. 20/2 = 10. 10² = 100. add 100 to both sides. and simplify x²-20x+100+15 to (x²-10)²+15. now subtract 100 from both sides to get y alone. this leaves you with y = (x²-10)-85. that's your vertex form.
Answer: it’s C
Step-by-step explanation:
She drives at a rate of 75 miles per hour for three hours, so the first thing you'd do is 75 x 3.
75 x 3= 225
So, she traveled 225 miles to the airport.
Then, she travels at a rate of 400 miles per hour for 4 hours.
4 x 400 = 1,600
That's 1600 miles she traveled from the airport to her destination.
Now to find the total number of miles traveled, add 1,600 and 225.
Total distance traveled: 1825 miles.