# HELP!polynomials:word problem equations

• Mar 18th 2009, 07:54 PM
Netquit
HELP!polynomials:word problem equations
Please show all work:

1)find the integers whose square is 36 more than 5 times itself

2) If x² is added to 7x, the sum is -12.What are possible values of x?

3)The area of a rectangle is 84 square inches. The length is 5 inches more than the width.Find the rectangle's length.

4) The area of a rectangle is 40 square meters. The width is 6 meters less than the length.Find the rectangle's width and length.
• Mar 18th 2009, 08:27 PM
Prove It
Quote:

Originally Posted by Netquit
Please show all work:

1)find the integers whose square is 36 more than 5 times itself

2) If x² is added to 7x, the sum is -12.What are possible values of x?

3)The area of a rectangle is 84 square inches. The length is 5 inches more than the width.Find the rectangle's length.

4) The area of a rectangle is 40 square meters. The width is 6 meters less than the length.Find the rectangle's width and length.

Where is YOUR work?
• Mar 19th 2009, 04:59 AM
stapel
Quote:

Originally Posted by Netquit
Please show all work:

As was gently suggested previously, it's really you who needs to "show all work". We already know how to do this stuff. (Wink)

The following should help in getting you started:

Quote:

Originally Posted by Netquit
1)find the integers whose square is 36 more than 5 times itself

"Integers" means "the whole numbers and their negatives". Pick a variable to stand for "the integer". Then translate "the square of the integer", "five more than the integer", and "thirty-six more than (five more than the integer)" into algebraic expressions. Use the "is" to create the equation, and then solve the quadratic equation.

Quote:

Originally Posted by Netquit
2) If x² is added to 7x, the sum is -12.What are possible values of x?

Create the expression representing the sum. Set the sum equal to the given value. Solve the quadratic equation.

Quote:

Originally Posted by Netquit
3)The area of a rectangle is 84 square inches. The length is 5 inches more than the width.Find the rectangle's length.

Since the length is defined in terms of the width, pick a variable for the width and then create an expression, in terms of this variable, for the length. Plug these into the formula for the area A of a rectangle with length L and width w. Also plug in the given value for the area A. Solve the resulting quadratic equation.

Quote:

Originally Posted by Netquit
4) The area of a rectangle is 40 square meters. The width is 6 meters less than the length.Find the rectangle's width and length.

This one works just like exercise (3). :D