Answer:
- (x - 3y)(3x + y)
Step-by-step explanation:
Given
(x + 2y)² - (2x - y)² ← expand both parenthesis using FOIL
= x² + 4xy + 4y² - (4x² - 4xy + y²) ← distribute
= x² + 4xy + 4y² - 4x² + 4xy - y² ← collect like terms
= - 3x² + 8xy + 3y² ← factor out - 1 from each term
= - 1(3x² - 8xy - 3y²) ← factor the quadratic
Consider the factors of the product of the coefficient of the x² term and the coefficient of the y² term which sum to give the coefficient of the xy- term.
product = 3 × - 3 = - 9 and sum = - 8
The factors are - 9 and + 1
Use these factors to split the xy- term
3x² - 9xy + xy - 3y² ( factor the first/second and third/fourth terms )
= 3x(x - 3y) + y(x - 3y) ← factor out (x - 3y) from each term
= (x - 3y)(3x + y)
Thus
(x + 2y)² - (2x - y)² = - (x - 3y)(3x + y)
Answer:
6
Step-by-step explanation:
y + 1
= 7
y +
= 
y = 40/6 = 20/3 = 6
Answer:
3rd option: B(C)= 1.79C +86.03
Step-by-step explanation:
Total bill
= cost of cans(number of cans) +cost of other groceries
Let the cost of other groceries be G, and the cost of cans be X.
Given that number of cans= C,
Total bill= XC +G
If 2 cans were purchased,
2X+G= 89.61 -----(1)
If 5 cans were purchased,
5X +G= 94.98 -----(2)
(2) -(1):
(5X +G) -(2X +G)= 94.98 -89.61
5X +G -2x -G= 5.37
3X= 5.37
X= 5.37 ÷3 <em>(</em><em>÷</em><em>3</em><em> </em><em>on</em><em> </em><em>both</em><em> </em><em>sides</em><em>)</em>
X= 1.79
Subst. X= 1.79 into (1):
2(1.79) +G= 89.61
3.58 +G= 89.61
G= 89.61 -3.58 <em>(</em><em>-3.58</em><em> </em><em>on</em><em> </em><em>both</em><em> </em><em>sides</em><em>)</em>
G= 86.03 <em>(</em><em>simplify</em><em>)</em>
Total bill
= XC +G
= 1.79C +86.03
Thus, the function is B(C)= 1.79C +86.03.
10 <0.25 (x + 1) <11
We must solve two inequalities in this case.
Inequality 1:
10 <0.25 (x + 1)
10 / 0.25 <x + 1
40 <x + 1
40-1 <x
39 <x
Inequality 2:
0.25 (x + 1) <11
(x + 1) <11 / 0.25
(x + 1) <44
x <44-1
x <43
The final result is:
39 <x <43
Answer:
39 <x <43
Answer: $7,605
Step-by-step explanation:
At the end of 1 years, the amount in the account will be:
= Principal * (1 + rate)^ no. of periods
= 6,500 * (1 + 17%)
= $7,605