Answer:
x=1/2or x=−3
Step-by-step explanation:
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
11 1/2+6 4/5 equals? So, you have to make each fraction have the same denominator. So, you would notice that they have in LCD (least common denominator )which is 10. So you're new fractions are 11 5/10+ 6 8/10. 11+6=17. 5/10+8/20=13/10. Which simplified it would be 1 3/10. 17+1 3/10 equals 18 3/10. 18 3/10 -3 3/10 equals 15. 15 is the answer.
Well if you're wanting to use substitution, you first have to end up with one term on either side of the equation. Use the second one as it's easiest.
So: x-2y=11, so find -2y as there is a -2y in the first equation.
then that becomes -2y=11-x. then sub that into equation 1, and you get:
-x+11-x=-13, which equals to -2x+11=-13, which is -2x=-24, so therefore
x=12. then chuck the x into any of the equations to find what y equals.
hope this helps!