Choosing a Method to Solve Quadratic Equations Practice 10

Question

Accepted Answer

Here, we need to solve this quadratic equation by determining the best method. Now, since we have a a value of something other than one, and our b value is odd, that tells me I probably want to go ahead and use the quadratic formula. So here our a value will be two, our b value is negative three, and our c value is negative five. Plugging these in we get negative negative b, so negative negative three, plus or minus the square root of b squared, negative three squared, minus four times a, so times two, times c, times negative five, all over two times a, so two times two. Simplifying, we have negative negative three is positive three. Negative three squared is nine. Negative four times two times negative five becomes plus forty, and two times two is four. So this will now be equal to three plus or minus the square root of nine plus 40 is 49, all divided by four. Now the square root of 49 is a perfect square, and it simplifies to seven. So we'll get two solutions. Our first is x will equal three plus seven, which is 10, divided by four, simplifies to five halves. And for our second solution, we'll have three minus seven, which is negative four, divided by four, which simplifies to negative one. These are the two solutions to this quadratic equation.

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Choosing a Method to Solve Quadratic Equations Practice 10

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