Posted by anonymos NEEDS HELP! on Thursday, August 21, 2008 at 11:33am.
Use any method to solve the following equations, giving your answers to 2 decimal places where necessary. If an equation has no real roots, state this is so.
1. x25x+7=0
2. (3x4)=(4x3)2

quadratic equations  math  Count Iblis, Thursday, August 21, 2008 at 11:58am
1. This is already in standard form. You should be able solve that equation from what you've learned.
2. Here it is convenient to substitute.
y = 4x3
Then
x = 1/4(y+3) >
3x  4 = 3/4 (y+3) 4 =
3/4 y  7/4
So, the equation is:
3/4 y  7/4 = y^2 >
4 y^2  3 y + 7= 0