Answer:
ans D
Step-by-step explanation:
area of rectangle is
l*b
(x+4)(x-2)
x^2-2x+4x-8
x^2+2x-8
Answer:
M(t) = 400•(0.79)^t
Step-by-step explanation:
As we can see, the change in mass is not uniform linearly
So it will be better if we used an exponential representation
The general form for an exponential representation is:
M(t) = I(1-r)^t
where r is the rate of decay, I is the initial value and t is the time in weeks with M(t) being the mass
Let us use any two points on the table
Thus, we have it that;
50 = 400(1-r)^9 •••••(i)
201 = 400(1-r)^3 •••••(ii)
divide i by ii
50/201 = (1-r)^6
0.249 = (1-r)^6
1-r = 6√0.249
1-r = 0.79
r = 1-0.79
r = 0.21
So the exponential equation is;
M(t) = 400•0.79^t
The function is only shifted vertically up 3 :)
Answer:
he had $90
he bought a phone for $75
90-75=15
he has $15 now
15÷0.06=1500÷6=250 minutes
Answer:
1) $350
2) 55°
3) $300
Step-by-step explanation:
1) The total cost is the cost of the appointment plus the cost of the repair work. The appointment costs $50. The repair work costs $120 per 2 hours. So the total cost is:
C = 50 + (120/2) t
C = 50 + 60t
For 5 hours of work, the cost is:
C = 50 + 60(5)
C = 350
It costs $350.
2) The temperature starts at 70°. It drops 10° in 4 hours. So the temperature after t hours is:
T = 70 + (-10/4) t
T = 70 − 2.5t
After 6 hours:
T = 70 − 2.5(6)
T = 55
The temperature is 55°.
3) Jennie's total pay is her weekly pay plus her commissions. If her commission is x% of her sales, then her pay is:
P = 250 + (x/100) S
When her sales is $1000, her pay is $275.
275 = 250 + (x/100) 1000
275 = 250 + 10x
25 = 10x
x = 2.5
So her pay is:
P = 250 + (2.5/100) S
When S = $2000:
P = 250 + (2.5/100) 2000
P = 250 + 50
P = 300
Her total pay is $300.