Solve each equation using the quadratic formula. See Examples 5 a...

Question

Solve each equation using the quadratic formula. See Examples 5 and 6. x^2 - 6x = -7

Accepted Answer

Hello, everyone. We're going to use the quadratic formula to find the value of X in the equation X squared minus 26 X plus 159 equals zero. I recall to use the quadratic formula. I want my equation to be set up as A X squared plus BX plus C equals zero. Looking at the equation I'm given it is already in that format. So I'm gonna define what my A B and C R A is. One, B is -26 and C is 159. I'm gonna write out what the quadratic formula is off to the side just to make it easier to plug in. Um It's X equals negative B plus or minus the square root of B squared -4 AC all over two a. So now that I have that all down, I'm gonna plug my values in. So X equals negative B or the opposite of B so positive 26 plus or minus the square root of B squared. So negative 26 squared minus four times A which is one times C which is 159 All over two times a so two times one. So next, I'm gonna do some of the multiplication that's under the radical 26 plus or minus stays put. Then I get the square root and negative 26 squared is a positive 676. And then when I do four times one times 159, I'm now subtracting Over two times 1 is two. I'm gonna combine what I have under my radical. So X square X equals 26 plus or minus the square root of when I subtract those I get 40 over to I need to reduce the radical of 40. So I'm gonna bring it over here just so I can space it out a little. Um I know that the perfect square of four is going to go into that times 10. So square to 40 is the same as square to four times square to 10. That would be two times the square to 10. I'm gonna plug that back into my equation. So now I have x equals 26 plus or - radical 10 over to and looking at this, I see that I can reduce each term by two. So I'm going to do so. So 26 divided by two is 13 plus or -2 radical 10, divided by two is just radical 10. So this means my two X values are 13 minus the square to 10 and 13 plus the square to 10. So those should be my solutions and checking over here that appears to be answer choice B have a nice day.

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Solve each equation using the quadratic formula. See Examples 5 and 6. x^2 - 6x = -7

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