SOLUTION: A building has an entry the shape of a parabolic arch 96 ft high and 18 ft wide at the base, as shown below. A parabola opening down with vertex at the origin is graphed on the c

Question 1135981: A building has an entry the shape of a parabolic arch 96 ft high and 18 ft wide at the base, as shown below.
A parabola opening down with vertex at the origin is graphed on the coordinate plane. The height of the parabola from top to bottom is ninety six feet and its width from left to right is eighteen feet.

Find an equation for the parabola if the vertex is put at the origin of the coordinate system.
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
A building has an entry the shape of a parabolic arch 96 ft high and 18 ft wide at the base, as shown below.
A parabola opening down with vertex at the origin is graphed on the coordinate plane. The height of the parabola from top to bottom is ninety six feet and its width from left to right is eighteen feet.
Find an equation for the parabola if the vertex is put at the origin of the coordinate system.
:
width of arch is -9 to +9. y intercept= 96. Using the form ax^2 + bx + c = y
x=-9,y=0. 81a - 9b + 96 = 0
x=+9,y=0. 81a + 9b + 96 = 0
-------------------------------addition eliminates b
resulting: 162a + 0 + 192 = 0
162a = -192
a = -192/162
a = -1.185
the equation: y = -1.185x^2 + 96
:
Looks like this

RELATED QUESTIONS
A building has an entry the shape of a parabolic arch 22 ft high and 28 ft wide at the... (answered by josmiceli)

A building has an entry the shape of a parabolic arch 22 ft high and 28 ft wide at the... (answered by josgarithmetic)

A building has an entry the shape of a parabolic arch 96 ft high and 18 ft wide at the... (answered by Alan3354)

A building has an entry the shape of a parabolic arch 74 ft high and 28 ft wide at the... (answered by josgarithmetic,MathTherapy)

An arch in the shape of a parabola has height 630ft and width 630ft. How wide is the arch (answered by MathLover1)

a bridge is built in the shape of a parabolic arch. the bridge has a span of 184 ft. and... (answered by greenestamps)

A parabolic arch is constructed which is 8 ft wide at the base and 9 feet tall. Find the... (answered by greenestamps)

An arch is in the form of a semiellipse. It is 48 ft wide at the base and has a height... (answered by MathLover1)

An arch is in the form of a semiellipse. It is 48 ft wide at the base and has a height... (answered by Alan3354)