Question

Urgent help!

Question: Write each of the following as an algebraic expression.
a. In a supermarket, beef is sold at $17.50 a kg. write an equation for the cost of buying (x)kg of beef from this supermarket.

b. Write an expression for the number that results when you think of a number 3x, and 5 to it and take the square root of the result.

c. Write an expression for the perimeter of a rectangle whose length is 4cm more than it's width which is (x)cm.​

Answer 1

a. y = 17.5x

b.
`√(3x + 5)`

c. 4x + 8

Explanation:

a.

Beef costs $17.50 per kg. That is a unit rate. To find the price of an amount x of beef, multiply the amount, x, by the unit rate.

y = 17.5x

b.

I think you may mean "add," not "and."

"Write an expression for the number that results when you think of a number 3x, add 5 to it and take the square root of the result."

The number is 3x.

Add 5 to it to get 3x + 5.

Take the square root to get

`√(3x + 5)`

c.

The width is x. The length is 4 cm more than x, so it is x + 4.

Length: x + 4

Width: x

perimeter = length + length + width + width

P = 2L + 2W

P = 2(L + W)

P = 2(x + 4 + x)

P = 2(2x + 4)

P = 4x + 8