Answer:
The possible number of CDs she could buy is 1, 2, and 3.
Step-by-step explanation:
First, you have to make an equation to solve to find the answer(s):
- 80 - (18 · x) ≥ 20
- 80 is how much money Felicia has; 18 is for the cost of each CD; x is for the number of CDs; ≥ is no less; and 20 is how much money Felicia needs to have left.
1.) 80 - (18 · 1) ≥ 20
80 - 18 · 1 ≥ 20
80 - 18 ≥ 20
62 ≥ 20
Since 62 ≥ 20 is always true, there are infinitely many solutions.
2.) 80 - (18 · 2) ≥ 20
80 - 18 · 2 ≥ 20
80 - 36 ≥ 20
44 ≥ 20
Since 44 ≥ 20 is always true, there are infinitely many solutions.
3.) 80 - (18 · 3) ≥ 20
80 - 18 · 3 ≥ 20
80 - 54 ≥ 20
26 ≥ 20
Since 26 ≥ 20 is always true, there are infinitely many solutions.
4.) 80 - (18 · 4) ≥ 20
80 - 18 · 4 ≥ 20
80 - 72 ≥ 20
8 ≥ 20
Since 8 ≥ 20 is false, there is no solution.
5.) 80 - (18 · 5) ≥ 20
80 - 18 · 5 ≥ 20
80 - 90 ≥ 20
- 10 ≥ 20
Since - 10 ≥ 20 is false, there is no solution.
Answer:
the only one that is a function is B
Step-by-step explanation:
the rest of them have repeating inputs which makes them no functions
Answer:
RD = 162 cm
Step-by-step explanation:
LD = 2 RL = 2* 54 = 108
RD = RL + LD
RD = 54 + 108
RD = 162 cm
A+bi is a complex number
(3+2i)(a+bi)=17+7i
remember
i²=-1
so
expand and solve
a is the ral part
bi is the imaginary part
ok so
if Ac+Be=dc+fe where c=c and e=e then A=d and B=f
(3+2i)(a+bi)=17+7i
expand/distribute/FOIL
3a+2ai+3bi+2bi²=17+7i
3a+2bi+2ai+2bi=17+7i
3a-2b+2ai+2bi=17+7i
real parts are 3a-2b
imaginary is 2ai+2bi
so
3a-2b=17 and
2ai+2bi=7i
we need to solve
2nd equation, divide both sides by i
2a+2b=7
multiply by -1 and add to other equation
3a+2b=17
<u>-2a-2b=-7 +</u>
1a+0b=10
a=10
subsitue
2a+2b=7
2(10)+2b=7
20+2b=7
2b=-13
b=-13/2
the complex number is
10-(13/2)i or
10-6.5i
Use this systems of equations to solve:
x = first antifreeze
y = second antifreeze
Isolate y.
x + y = 15
Subtract x from both sides.
y = -x + 15
Substitute y into the other equation.
.2x + .12(-x + 15) = .18(15)
Simplify.
.2x - .12x + 1.8 = 2.7
Subtract 1.8 from both sides.
.08x = .9
Divide both sides by .08
x = 11.25
Substitute x in the equation that we isolated y in.
y = -11.25 + 15
y = 3.75
11.25 L of the first antifreeze and 3.75 L of the second.
