Answer:
3s + 7.99 = 71.83
Step-by-step explanation:
Yeah, algebra sure confused me the first time I took it. I had a much more patient and engaging teacher the second time!
How would we find out in real life how much each shirt cost? We'd subtract 7.99 from 71.83 and divide the difference by 3, right??
Let's work that backward. Let's say a shirt cost $6. Three would cost $3(6), or $18. Since each shirt costs $s, our price for 3 shirts is $3s. We have to add shipping to get a total, which we are given. When writing an equation, we leave out labels like $ or meters or books or whatever.
That would be choice 2. One acute angle is the complement of the other
eg in a 90-60-30 triangle sine 30 = cos 60
the example of an open equation is :x+9=16
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
Answer:
x = 14
Step-by-step explanation:
comp = add up to be 90
3x + 14 + 2x + 6 = 90
5x + 20 = 90
5x = 70
x = 14