Answer:
k can either be
12
or
−
12
.
Step-by-step explanation:
Consider the equation
0=x2+4x+4
. We can solve this by factoring as a perfect square trinomial, so
0=(x+2)2→x=−2 and−2
. Hence, there will be two identical solutions.
The discriminant of the quadratic equation (b2−4ac) can be used to determine the number and the type of solutions. Since a quadratic equations roots are in fact its x intercepts, and a perfect square trinomial will have
2 equal, or 1
distinct solution, the vertex lies on the x axis. We can set the discriminant to 0 and solve:
k2−(4×1×36)=0
k2−144=0
(k+12)(k−12)=0
k=±12
Answer:
The plans will cost the same when the amount you have to pay for talking for "x" minutes on Plan A is the same has what you have to pay for talking for the same number of "x" minutes when using Plan B.
$$ Plan A = $$ Plan B
To find the charge on each plan we add the base rate to the per minute call rate for each.
Plan A = $27 + $0.11x
Plan B = $13 + $0.15x
Let's drop the $ sign for now and get rid of the decimal point by multiplying by 100.
2700 + 11x = 1300 + 15x
Subtracting 11x and 1300 from both sides:
4x = 1400
x = 350 min.
Using this result the plans both cost $65.50 for 350 min of talk time.
Step-by-step explanation:
boom :)
If it is a ratio of 3:5 you are dividing 480 into 8 parts (3+5).
So divide 480 by 8: 480/8 = 60
Then the ratio is (3x60):(5x60) or 180:300
To check it is correct, add up the two parts to see that they come to 480:
180+300 = 480. All good.
Hope this helps
Answer: $37.20
Step-by-step explanation:
Just add those 2 amounts together
Answer:
x = 6
Step-by-step explanation:
cross multiplication and a wild guess
