Answer:
A parallelograms are rectangles
C=1500+4x where x is cds, C is cost
R=10x where R is revenue
then, P=R-C
P=10x-1500-4x
P=6x-1500
set P=0
1500=6x
x=250
check, C=1500+4*250, R=10*250
C=250, R=250
They need to sell 250 cds before they make profit
Explanation
The model has the form
Where a=initial amount
y= final amount
K= growth rate constant
t= time
When 140 kg of substance is left after 7 hours, the formula can be remodeled to be.
Therefore, the first solution is
For part b we have 16 hours.
Thus, the answer is 36kg
Answer:
Depends on what way you learnt it
Step-by-step explanation:
x + y = 4. x^2 + y^2 = 28. These are the given equations.
Square the first equation to get x^2 + 2xy + y^2 = 16.
Subtract the new equation from x^2 + y^2 = 28 to get 2xy = -12.
Divide by 2 to get xy = -6. The questions asks for positive numbers, and a positive times a positive is not a negative, therefore there are no two numbers.
Answer:
10x + 12 and 6x² + 11x - 7
Step-by-step explanation:
The perimeter (P) of a rectangle is calculated as
P = 2l + 2w ( l is length and w is width )
= 2(2x - 1) + 2(3x + 7) ← distribute parenthesis
= 4x - 2 + 6x + 14 ← collect like terms
= 10x + 12
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The area (A) of a rectangle is calculated as
A = lw
= (2x - 1)(3x + 7) ← expand using FOIL
= 6x² + 14x - 3x - 7 ← collect like terms
= 6x² + 11x - 7