Answer:
x = 1.8
Step-by-step explanation:
5x - - 5x makes 5x+5x which is equal to 10x
10x+21= 39
-21 -21
10x= 18
10x/10 = 18/10
x = 1.8
One gallon costs $1.88. To find the cost of seven gallons, you would multiply this price by seven.
1.88 x 7 = $13.16, which is answer D
Answer:
17m
Step-by-step explanation:
Draw a picture for the situation:
__________<u>15m</u>___________
| |
b | | 8m
|________________________|
a
We can assume the floor is a rectangle. Cut the triangle diagonally in half.
The rectangles has all right angles and is composed of two right triangles.
Use the Pythagorean formula and solve for the length of the hypotenuse to find the distance between two the opposite corners. I labelled two of the sides a and b.
The formula is: a² + b² = c² , where c is the distance. Substitute the side lengths a and b and solve for c.
a² + b² = c²
15² + 8² = c²
Simplify:
225 + 64 = c²
c² = 289
c = √289
c = 17
The distance between two opposite corners on the floor is 17 metres.