a)
Let t represents number of years after 1900
so that means for 1900, value of t is 0
We are given point as (0,55)
and it says that life expectancy increases by 0.2
so that means slope,m=0.2
equation of line is y=mt +b
or y=0.2t +b
now we use point (0,55)
55 =0.2(0) +b
55 =0+b
55= b
so b=55
plug it back into the equation,we get
y=0.2t +55
b)
We are given y=73
so we plug it into the equation we got in part a and solve for t
y=0.2t +55
73 =0.2t +55
73-55 =0.2t
18 =0.2t
18/0.2 =t
90 =t
so t=90
This means the birth year =1900+t =1900+90 =1990
Answer:

Step-by-step explanation:
we know that
----> by supplementary angles (form a linear pair)
Solve for x
Combine like terms

subtract 99 both sides

Divide by 3 both sides

Here are some things you should know when solving algebraic equations.
If you add an expression to both sides of an equation, the resulting equation will have the same solution set as the original equation. In other words, they will be equivalent. This is true for all operations. As long both sides are treated the same, the equation will stay balanced.
You will also need to know how to combine like terms. But what are like terms to begin with? Like terms are defined as two terms having the same variable(s) (or lack thereof) and are raised to the same power. In mathematics, something raised to the first power stays the same. So, 5x and 10x are like terms because they both have the same variable and are raised to the first power. You don’t see the exponents because it doesn’t change the value of the terms.
To combine like terms, simplify add the coefficients and keep the common variable(s) and exponent.
The distributive property is another important rule you will need to understand.
The distributive property is used mostly for simplifying parentheses in expressions/equations.
For example, how would you get rid of the parentheses here?
6(x + 1)
If there wasn’t an unknown in between the parentheses, you could just add then multiply. That is what the distributive property solves. The distributive property states that a(b + c) = ab + ac
So, now we can simplify our expression.
6(x + 1) = 6x + 6
Now let's solve your equation.
9v = 8 + v
8v = 8 <-- Subtract v from each side
v = 1 <-- Divide both sides by 8
So, v is equal to 1.
Answer:
B. In step 2, marquis should have interpreted the results as x _< - 9.2, which means that x is less than or equal to -9.2
Step-by-step explanation:
Step 1 is correct.
Step 2.
-9.2 >= x
Subtract x from both sides.
-x - 9.2 >= 0
Add 9.2 to both sides.
-x >= 9.2
Divide both sides by -1. When you multiply or divide both sides of an inequality, the inequality sign changes direction.
x <= -9.2
The first error is in Step 2.
Answer:
B. In step 2, marquis should have interpreted the results as x _< - 9.2, which means that x is less than or equal to -9.2