00:01
So in this problem, it says the length of a rectangle is 19 centimeters less than four times the width.
00:07
So i'm going to go ahead and label the width here as x.
00:10
And i'm going to label the length as 4x minus 19, since it's 19 less than four times the width.
00:21
And it tells us that the area is 63 centimeters squared.
00:28
So i'm going to go ahead and multiply these together, since the formula, upper areas length times width and set them equal to 63.
00:36
So that's 63 equals x times 4x minus 19.
00:44
And then from here, i'm going to go ahead and distribute.
00:48
So i have 63 equals 4x squared minus 19x.
00:54
And then i'm going to subtract the 63 to the other side to try to factor.
01:06
Now from here, i'm going to multiply my a value by my c value.
01:10
So 4 times negative 63 is 252.
01:15
So i need two numbers that multiply to 252 and add to negative 19...