Help please! I dont just want the answer. I need someone to help me through it! A square picture frame occupies an area of 112 ft2. What is the length of each side of the picture in simplified radical form?
The area is 112. Let the length of a side be x. So what is our equation that we have about the picture frame?
Im really not sure @Nory
would 112 ft. 2 be 112^2? @Nory
The area of the frame is 112, but it is also x*x (because of the area of the rectangle.) So our equation would be x^2 = 112. Do you know how to solve this equation?
wouldnt that equation turn into x^2 - 112? @Nory
Yes, but there's an easier way to solve it. Go back to x^2 = 112 and take square roots of both sides. What do you get?
square root of 112 is 10.583? and x^2 is 2.718
@Nory
Write it as a radical. x = √122 x is the length of a side.
Oh wait, 112. Not 122. What am I thinking?
haha its okay. so x = the square root of 112? which is 10.583?
@Nory
@jim_thompson5910 could you help me?
can you factor 112 where one factor is a perfect square
yes?
how so
you have to find a number that can be multiplied with another to get 112
yep
ex: 112 = 2*56 but neither factor is a perfect square
i dont get how you find out if a number is a perfect square.
it might help to list out the perfect squares (up to 112) 1, 4, 9, 16, 25, 36, 49, 64, 81, 100
so i would find the best perfect square you can divide out of 112?
so for instance, 9 is NOT a factor since 112/9 = 12.4444
it would be a factor if you got a whole number when you divided
so the number it equals would have to be a whole number?
yes if you divided and got a whole number, then the number you divided by is a factor
ex: 112/2 = 56, so this means 2 is a factor of 112 it also means 56 is a factor as well
but neither are perfect squares
im so confused
do you see how 2 is a factor of 112?
so 56 and 2 are not perfect squares because their square roots are not whole numbers?
exactly
25 is a perfect square because the square root of 25 is 5 (a whole number)
so i have to find a number that is a factor of 112 and is also a perfect square?
exactly
and you want to find the largest possible factor that's a perfect square
okay so the largest number is 16?
yep good
so 112/16 = ???
7
this means that 112 = 16*7
so each side is 7?
and this further means.... \[\large \sqrt{112} = \sqrt{16*7}\] \[\large \sqrt{112} = \sqrt{16}*\sqrt{7}\] \[\large \sqrt{112} = 4\sqrt{7}\]
notice how I simplified by exploiting the fact that you can factor where one factor is a perfect square (the largest perfect square possible)
yea you got 4. so i have to simplify 16 to finish the equation?
yes you have to take the square root of 16 to get 4
this was easier then I thought! thank you once again!
yw
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