Step-by-step explanation:
#1.
(a + 2b)²
<em>Using identity (x + y)² = x² + 2xy + y², we get:</em>
= (a)² + (2b)² + 2 × (a) × (2b)
= a² + 4b² + 4ab
= a² + 4ab + 4b² Ans.
#2.
(5x - 3y)²
<em>Using identity (a - b)² = a² - 2ab + b², we get:</em>
= (5x)² + (3y)² - 2 × (5x) × (3y)
= 25x² + 9y² - 30xy
= 25x² - 30xy + 9y² Ans.
#3.
(3a + 4)(3a - 4)(9a² + 16)
<em>Using identity (x + y)(x - y) = x² - y², we get:</em>
= [(3a)² - (4)²][9a² + 16]
= (9a² - 16)(9a² + 16)
= (9a²)² - (16)²
= 81a⁴ - 256 Ans.
Answer:
<em>The man paid $200 for the cow</em>
Step-by-step explanation:
<u>System of Equations</u>
Let's call:
x = price of the cow
y = price of the horse
The man bought the cow and the horse for $500, thus
x + y = 500 [1]
The cow was sold at a profit of 10%, thus:
Sale price of the cow= 1.1x
The horse was sold at a loss of 10%, thus:
Sale price of the horse= 0.9y
The total operation was a 2% loss, i.e. 0.98*500=490. Thus, we have:
1.1x + 0.9y = 490 [2]
From [1]:
y = 500 - x
Substituting in [2]:
1.1x + 0.9(500 - x) = 490
Operating:
1.1x + 450 - 0.9x = 490
0.2x = 490 - 450 = 40
x = 40/0.2
x = 200
The man paid $200 for the cow
Answer:
40% of the total was spent on fruit
Step-by-step explanation:
100%=45 x=18
100/x = 45/18 Now take the inverse of both sides
x/100 = 18/45
This leads to 1800 = 45x
1800 divided by 45 is equal to 40
The total percentage spent on fruit was 40%
Answer:
I don't know if I'm right at all
x 1/2 2
5 × x2 ^
It's the y intercept.
If y = a then every point on the line would be (x,a)
The lines slope is 0. I know that has nothing to do with the question, but it is true and it gives me 3 things to tell you.
