Surface Area of Pyramids Instructions: Find the surface area of each figure. Round your answers to the nearest tenth, if necessary.

9514 1404 393

  288 km²

Step-by-step explanation:

The surface area is the sum of the area of the square base and the area of the four triangular faces.

  SA = (10 km)² + 4(1/2)(10 km)(9.4 km) = 288 km²

The area formulas for a square and a triangle are ...

  A = s² . . . . area of a square of edge length s

  A = 1/2bh . . . . area of a triangle with base b and height h

f(x) has value 150 at x= 0

and 0 at x= 3

so d(f(x))/dt = slope = -150/3 = -50

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