Quadratic Word Problems | MathHelp.com

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A number is 56 less than its square. Find the number. To solve this problem, let’s translate the first sentence into an equation. A number, that’s x, is, =, 56 less than it’s square, that’s x squared – 56. Remember that “less than” switches the order around. In other words, “56 less than its square” is not 56 minus x squared, it’s x squared minus 56. Next, since we have an x squared term in our equation, we set it equal to 0 by subtracting x from both sides, and we have 0 = x squared – x – 56. Next, we factor the right side as the product of two binomials. In the first position of each binomial, we have the factors of x squared, x and x. In the second position of each binomial, we’re looking for the factors of -56 that add to -1, which are -8 and positive 7. So we have 0 = x - 8 times x + 7, which means that either 0 = x – 8 or 0 = x + 7. Finally, in the first equation, we add 8 to both sides, to get 8 = x. And in the second equation, we subtract 7 from both sides, to get -7 = x. So 8 = x or -7 = x. It’s important to understand that both of these answers work. Plugging an 8 back into the original problem, we have 8 is 56 less than 8 squared, or 8 = 8 squared – 56, which simplifies to 8 = 64 – 56, or 8 = 8, which is a true statement. And plugging a -7 back into the original problem, we have -7 is 56 less than -7 squared, or -7 = -7 squared – 56, which simplifies to -7 = 49 – 56, or -7 = -7, which is also a true statement.

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This account still exist, I remember using my moms phone and account just to learn

kusuo
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you gata be kidding me you, I learnt maths from this channel when I was a boi/kid yada yada yada
but this channel still exist I mean
WTF?

jeytube
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Please bring back that guy bro he was so relatable to me💀💀💀

WavyDog
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their complete lack of enthusiasm helps them become immortal beings

arthurslavit
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i remember using this channel it was so gay to me 💀💀💀💀💀💀

RiotheSaiyan
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You can also use the quadratic formula to find the roots of x sub 1 and x sub 2.

jayveeaurea
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What sort of math editor do they use, or a tool used to create this the math equation?

wittawatburutrkhaeliso
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im going to senior high grade 11 in less than 2 month this channel might help me

dempzei
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Thank you so many I have a test tomorrow I think I’m gonna beat it thanks to you
✨✨👁👄👁✨✨

katiaciss
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So on a ti83 I go to plot for a function then option9 then yvars function to enter the intervals but when I hit enter it takes me to Y2. I can't get a answer. The enter works for regular calculation.

WResearcher
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Man I remember when this video helped me so much in high school, now kids are using AI like Digihomelearning to get help

Itskingmonty
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What is the answer of 0.9/ 81.
Please answer. Thank you

mothertheresa
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In india this is ask for only for 1 marks and it is sloved by 8 standard child

Flywithme