X+y+z=5

-2x-3y+2z=8

3x-y-2z=3

Multiple Choice In Mr. Mamer's math class, there are three times as many girls as boys. The girls' mean grade on a recent quiz was 90, and the boys' mean grade was 86. What was the mean grade for the entire class? F. 88 G. 44 H. 89 J. 95

Write a word problem involving money that requires dividing a decimal by a whole number including estimate and a solution

The formula for (a-b) ^2 is a^2-2ab+b^2. (x-2) ^2=x^2-2*x * (-2) + 4 =x^2+4x+4 I solved this. Why is not correct to take the second number negative? I mean, the solution for the exercise is x^2-4x+4. Why is it negative instead of positive?

If a car is traveling 65 miles per hour then how many miles will the car travel in 1.5 hours

A triangular prism has an equilateral base with side length x inches. The height of the prism is four times as long as the side length. What is the lateral area of the prism? 12x square inches 12x2 square inches 36x square inches 36x2 square inches

What is 8.49x10^-7 in decimal form? 0.0000000849 0.000000849 8,490,000 849,000,000

Travel Ez sells dollars at a rate of ($1.40) / (1 euro) and buys dollars at a rate of ($1.80) / (1 euro). At the beginning of a trip, Sophie exchanged $540 to get 300 euros.

What is the range of y = square root x+7+5?

Is to a solution of the equation 3x+6=6x?

What would - 9 1/2 be as a decimal?