Answer: Each adult’s meal costed $15
Step-by-step explanation:
This situation can be modeled by the following equation:
2a + 3c = 42, where a = the cost of an adult’s meal, and c = the cost of a child’s meal
Since we know from the problem that a child’s meal costs $4, we know c:
2a + 3(4) = 42
At this point, we can just solve the resulting equation for a:
2a + 3(4) = 42
= 2a + 12 = 42 (simplify 3(4))
= 2a = 30 (subtract 12 from both sides)
= a = 15 (divide both sides by 2)
So, the cost of each adult’s meal was $15.
Answer:
Step-by-step explanation:
x^2 + 3x - 9 =0
By comparing with the equation ax^2+bx+c = 0,
we get,
a = 1, b=3, c = -9
we know the formula for x is,
x = (-b±√(b^2 - 4ac))/2a
x = (-3±√45)/2
x = (-3±3√5)/2
x = (-3+3√5)/2, (-3-3√5)/2
Answer:
300
Step-by-step explanation:
The red portion is marked with a small square; that means it is a 90° section. It is 1/4 of the whole circle. They also said 75 kids chose red. If 1/4 of the circle represents 75 kids, then the whole entire circle would represent 75+75+75+75 kids or 4(75) kids, which is 300 kids.
Given a group of
n object. We want to make a selection of
k objects out of the n object. This can be done in
C(n, k) many ways, where
,
where k!=1*2*3*...(k-1)*k
Thus, we can do the selection of 3 cd's out of 5, in C(5,3) many ways,
where
Answer: 10
