SOLUTION: I need help with finding all intercepts for the graph of the quadratic function f(x) = 5x² - 38x + 21

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Question 382653: I need help with finding all intercepts for the graph of the quadratic function
f(x) = 5x² - 38x + 21
Answer by kingme18(98) About Me  (Show Source):
You can put this solution on YOUR website!
x-intercepts can be found by setting y=0, and y-intercepts are when x=0.
The y-intercept is easier to find: f%280%29=5%2A0%5E2-38%2A0%2B21=21, so the y-intercept is 21.
To find the x-intercepts: 0=5x%5E2-38x%2B21. We can solve by factoring: 0=%285x-3%29%28x-7%29. If two things multiply to 0, one of them must be equal to 0. Thus, either 5x-3=0 or x-7=0. To solve the first equation, add 3 to both sides then divide by 5, so x=3%2F5. To solve the second, add 7 to both sides and get x=7. This means your x-intercepts are 3/5 and 7.