77(7) = 539, the total points of all her tests
539 - 18 + 81 = correct total points = 602
602/7 = 86 which is the new average
Length times width times height
Answer:
y = 0.265x - 494.7
Step-by-step explanation:
Let median age be represent by 'a' and time be represent by 't'
In 1980, median age is given 30
which means that
a₁ = 30
t₁ = 1980
In 2000, the median age is given 35.3
which means that.
a₂ = 35.3
t₂ = 2000
The slope 'm' of the linear equation can be found by:
m = (a₂ - a₁) /(t₂ - t₁)
m = (35.3 - 30)/(2000-1980)
m = 0.265
General form of linear equation is given by:
y = mx + c
y = 0.265x +c
Substitute point (1980,30) in the equation.
30 = 0.265(1980) + c
c = -494.7
Hence the the linear equation can be written as:
y = mx + c
y = 0.265x - 494.7
-3, 3, 5.
https://www.wolframalpha.com/input/?i=%28x%5E3%29-%285x%5E2%29-9x%2B45%3D0