Answer:
Step-by-step explanation:
hello :
a(x) = 3x - 12 and b(x) = x-9, so
a[b(x)]=a(x-9) =3(x-9)-12
a[b(x)]=3x-9-12
a[b(x)]=3x+21
Sixty more than ninety times two multiply by x
Answer: 10, 11, & 12
<u>Step-by-step explanation:</u>
Let x represent the age of the youngest child.
Their ages are consecutive so,
Youngest: x
Middle: x + 1
Oldest: x + 2
The age of the Youngest squared (x²) equals 8 times the Oldest [8(x + 2)] plus 4.
x² = 8(x + 2) + 4
x² = 8x + 16 + 4
x² = 8x + 20
x² - 8x - 20 = 0
(x - 10)(x + 2) = 0
x - 10 = 0 or x + 2 = 0
x = 10 or x = -2
Since age cannot be negative, x = -2 is not valid
So, the Youngest (x) is 10
the Middle (x + 1) is 11
and the Oldest (x + 2) is 12
Given:
- Bought n items of product A at 1/5 rs each
- bought n items of product B at 1/4 rs each
He mixed the two items and sold each at 2/9 rs each.
He lost 3 rs in the above batch of articles.
Solution:
revenue = 2n* (2/9) rs = 4n/9 rs
cost = n/5+n/4 rs = n(1/5+1/4)
Profit = revenue-cost = 4n/9-n(1/5+1/4) = -3 rs
Solve for n
4n/9-n(1/5+1/4) = -3
factor out n
n(4/9-1/5-1/4)=-3
n(80-36-45)/180=-3
-n/180=-3
n=3*180=540
Total number of products bought
= n+n = 540+540 = 1080
You add 2x and 7x to get 9x
so the answer is 9x+5y
