9514 1404 393
Answer:
9(x +y)
Step-by-step explanation:
You observe that both terms have a coefficient of 9. The distributive property lets you factor that out, so you can rewrite the expression as ...
9x +9y = 9(x +y)
_____
It might help to think of parentheses as a "bag." The expression 9(x+y) tells you the contents of one bag is (x+y) and you have 9 of them. You could think of x, and y as representing two different physical objects, for example, perhaps a ball and a cube.
The first expression, 9x +9y, tells you that you have 9 of each of these objects. The distributive property says this could be the result of dumping the contents of 9 bags, each containing one each of the objects. The expression 9(x+y) is the version of the expression that shows these objects as being grouped into 9 bags.
The answer is x = 10, y = 10.
Step 1: rearrange the second equation for y.
Step 2: substitute y from the second equation into the first equation.
Step 3. Calculate y.
Step 1.
<span>The second equation is: 6x + 3y = 90
Divide both sides of the equation by 3:
(6x + 3y)/3 = 90/3
6x/3 + 3y/3 = 30
2x + y = 30
Rearrange the equation:
y = 30 - 2x
Step 2.
</span>Substitute y from the second equation (y = 30 - 2x) into the first equation:
<span>15x + 9y = 240
15x + 9(30 - 2x) = 240
15x + 270 - 18x = 240
15x - 18x = 240 - 270
-3x = -30
x = -30/-3
x = 10
Step 3.
Since </span>y = 30 - 2x and x = 10, then:
y = 30 - 2 * 10
y = 30 - 20
y = 10
Answer:
false
Step-by-step explanation:
foci are usually in the ellipse. that foci is where the ellipse is drawn from