A slice is made parallel to the base of a right rectangular pyramid as shown.
What is the area of the resulting two-dimensional cross- section? 5 in wide 4in width cross section 2.5 wide 2in width 7in height

5x + 3y = - 4

step-by-step explanation:

the equation of a line in standard form is

ax + by = c ( a is a positive integer and b, c are integers )

express the line first of all in slope- intercept form

y = mx + c ( m is the slope and c the y-intercept )

to calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (7, - 3) and (x₂, y₂ ) = (4, - 8)

m = = -

y = - x + c ← is the partial equation

to find c substitute either of the 2 points into the partial equation

using (4, - 8 ), then

- 8 = - + c ⇒ c = -

y = - x - ← in slope-intercept form

multiply all terms by 3 to eliminate the fractions

3y = - 5x - 4 ( add 5x to both sides )

5x + 3y = - 4 ← in standard form

part a: 1.08

part b: 27.59

step-by-step explanation:

the triangles are similar. therefore the corresponding sides are in proportion:

              cross multiply

            divide both sides by 32

we can set up an equation to find the girls' ages. the equation is         28=0.5x-5+x. (comment if you need me to explain how i got this equation.) so, you add x and 0.5x to get 1.5x and add 5 to each side. your new equation is 33=1.5x. now divide both sides of the equation by 1.5 to get 22=x. because x is mary's age, to find jasmine's age we subtract mary's age from 28. we find that mary is 22 years old and jasmine is 6 years old.