Answer:
(B)
4 +/- 3 sqrt(2) or 4+3sqrt(2) and 4-3sqrt(2)
Step-by-step explanation:
4(c-4)^2=72
4(c-4)(c-4)=72
foil the parenthesis (first, outside, inside, last)
4(c^2 -4c -4c +16)=72
4(c^2-8c+16)=72
divide each side by 4
c^2-8c+16=18
subtract 18 from both sides
c^2-8c-2
use quadratic formula
((-b +/- sqrt((-b^2)-4ac)))/2a
((-(-8)+/-sqrt((-8)^2-4(1)(-2)))/2(1))
(8+/-sqrt(64-(-8)))/2
(8+/-sqrt(64+8))/2
(8+/-sqrt(72))/2
(8+/-sqrt(36 * 2))/2
(8+/-6sqrt(2))/2
4+/-3sqrt(2)
or 4+3sqrt(2) and 4-3sqrt(2)
Answer:
2x+1y
Step-by-step explanation:
because a variable (the letter) is always 1, in that case 1 + 1 is 2 and 1 x 1 is 1. but since x and y are two different letters you cannot add them. hoped that helped :)
Answer:
A function is a relation in which each element of the domain, or x-value, is mapped to one element of the range, or y-value.
The question we are asked is if cost is a function of the activity type. This means that cost would be the range and activity type would be the domain.
If this is a function, then each activity type would have only one cost. However, on different days of the week each activity type has different prices; this means there is more than one cost for each activity type, and it is not a function.
Answer: 46 years
Step-by-step explanation:
Let the father's age be x and the son's age be y, then 3 years ago:
Father = x - 3
son = y - 3
Then , from the first statement :
x - 3 = 3 ( y - 3 )
x - 3 = 3y - 9
x = 3y - 9 + 3
x = 3y - 6 .......................................... equation 1
In five years time
father = x + 5
son = y + 5
Then , from the second statement
x + 5 = 2 ( y + 5 )
x + 5 = 2y + 10
x = 2y + 10 - 5
x = 2y + 5 ........................ equation 2
Equating equation 1 and 2 , we have
3y -6 = 2y + 5
add 6 to both sides
3y = 2y + 5 + 6
subtract 2y from both sides
3y - 2y = 11
y = 11
substitute y = 11 into equation 1 to find the value of x
x = 3y - 6
x = 3(11) - 6
x = 33 - 6
x = 27
This means that the father is presently 27 years and the son is presently 11 years.
In four years time
father = 27 + 4 = 31
son = 11 + 4 = 15
sum of their ages in four years time will be
31 + 15 = 46 years