Answer:
<h2>30</h2>
Step-by-step explanation:
<h3>to understand the steps</h3><h3>you need to know about:</h3>
- system of linear equation
- word problems
- PEMDAS
first step
let's create the equation word problem
<h3>my mother's current age is four times the sum of the ages of my two sisters. After 5 years, my mother's age will be double the sum of the ages of my two sisters. What is the current age of my mother? (imaginary problem)</h3>
let's solve
let my mother's and sister's age be x and y respectively
according to the first condition,x=4y....(I)
according to the 2nd condition,x+5=2(y+5×2).....(ii)
so the system of linear equations is
x=4y
x+5=2(y+5×2)
gets from the second equation
x+5=2(y+10)
x+5=2y+20
4y+5=2y+20 (as x=4y)
2y=15
y=7.5
so the age of mother is
x=4.(7.5)
x=30
Work shown above! Answer is C
Answer:
f(-3)=3
Step-by-step explanation:
We know that f(x)=-2x-3. In order to find f(-3), we simply need to substitute x with -3.
Thus, we have:
=-2(-3)-3
=6-3
=3
Answer:
-12 - 10i.
Step-by-step explanation:
-9 - 8i - (3 + 2i)
= -9 - 8i - 3 - 2i
= -12 - 10i.