Answer:
Step-by-step explanation:
Let's call lifeguarding L and car washing W. In order to write a system, we need to first separate the NUMBER of hours worked from the MONEY earned, because they are very different things.
If she works 10 hours, that is the number of hours worked between both jobs. Therefore, the equation for the NUMBER of hours worked is
L + W = 10.
If she earns $13 an hour lifeguarding, the expression for that is 13L; if she earns $12 an hour car washing, the expression for that is 12W. The MONEY she earned together by doing both those jobs is
13L + 12W = 124
There you go!
Step-by-step answer:
Given:
Circle C1: x^2+y^2 = 45
Line L1: -3x+y=15
Need to find the points of intersection.
Solution:
basically we need to solve for the roots of equations C1 and L1.
Here, we can use substitution of L1 into C1.
Rewrite L1 as : y=3x+15
substitute into C1:
x^2+(3x+15)^2 = 45
Expand
x^2 + 9x^2+90x+225 = 45
Rearrange terms:
10x^2+90x+180 = 0
Simplify
x^2+9x+18 = 0
Factor
(x+6)(x+3) = 0
so
x=-6 or x=-3
Back-substitute x into L1 to calculate y:
x=-6, y=3*x+15 = 3(-6)+15 = -3 => (-6,-3)
x=-3, y=3*x+15 = 3(-3) + 15 = 6 => (-3, 6)
Therefore the intersection points are (-6,-3) and (-3,6)
Check using equation C1:
(-6)^2+(-3)^2 = 36+9 = 45 ok
(-3)^2+(6)^2 = 9 + 36 = 45 ok
Check using equation L1:
Point (-6,-3) : y = 3x+15 = 3(-6) +15 = -3 ok
Point (-3,6) : y = 3x+15 = 3(-3)+15 = 6 ok.
Answer:
How many board games have you played in the past month, How many board games require a deck of cards to play, In what aisle are the board games located in the local store
Answer:
Because of the cross quitients of the protion are equal
Step-by-step explanation:
Answer:
3 outcomes
Step-by-step explanation:
