Answer: $19.6
Step-by-step explanation:
Linear function: f(x)=mx+c
, where m= rate of change in f(x) with respect to x.
c = Initial value.
Let c = Initial value of card , m= Charge per minute
x= Number of minutes calling time.
Then, 25.06= 38m+c (i)
21.03=69m+c (ii)
Eliminate (ii) from (i)

Put m in (i) , we get

i.e. f(x)=-0.13x+30
if x=80 then
f(80)= -0.13(80)+30
=-10.4+30
=19.6
Hence, the remaining credit after 80 minutes of calls = $19.6
Answer: 
Step-by-step explanation:
Given
Complex number is 
Its conjugate is obtained by changing the sign of the original number i.e. 
The product of the two numbers is
![\Rightarrow (2-i5)(2+i5)=2^2-(5i)^2\quad \quad [(x+y)(x-y)=x^2-y^2]\\\\\Rightarrow (2-i5)(2+i5)=4-25i^2\\\\\Rightarrow (2-i5)(2+i5)=4+25=29](https://tex.z-dn.net/?f=%5CRightarrow%20%282-i5%29%282%2Bi5%29%3D2%5E2-%285i%29%5E2%5Cquad%20%5Cquad%20%5B%28x%2By%29%28x-y%29%3Dx%5E2-y%5E2%5D%5C%5C%5C%5C%5CRightarrow%20%282-i5%29%282%2Bi5%29%3D4-25i%5E2%5C%5C%5C%5C%5CRightarrow%20%282-i5%29%282%2Bi5%29%3D4%2B25%3D29)
Answer:
=2*3^2 *7
Step-by-step explanation:
Prime factorization means to simplify 126 down to prime numbers
126 = 2*63
= 2* 9*7
= 2*3*3*7
Since 2 3 and 7 are prime numbers, we rewrite these with exponents
=2*3^2 *7
Answer
899
Step-by-step explanation:
99
45/3=15 45-15=30 30/5=6 3x6=18 30-18=12 the answer is 12