Which statements are true the ordered pair (1, 2) and the system of equations? y=−2x+4
7x−2y=3

Select EACH correct answer.

When (1, 2) is substituted into the first equation, the equation is true.
When (1, 2) is substituted into the first equation, the equation is false.
The ordered pair (1, 2) is not a solution to the system of linear equations.
When (1, 2) is substituted into the second equation, the equation is false.
When (1, 2) is substituted into the second equation, the equation is true.
The ordered pair (1, 2) is a solution to the system of linear equations.

The following are true:-

First choice

Third choice.

The last choice

(1,2)  is a solution to the system of equations

Step-by-step explanation:

answer: ratio of volume of cone (with 3 times the height and equal diameter) to volume of cylinder is 2 to 1. the value of π is not used.

step-by-step explanation:

radius is diameter/2 = 4.

area of circle is π r^2.

volume of cylinder is height × area of base = hπr^2 = 3(4^2) π = 48π cubic inches.

not knowing the formula for volume of cone, i calculate it using calculus (which is for calculating things).

volume of cone is integral 0 to h area(y) dy. area(y) is π r(y)^2. r(y) runs r to zero as y runs zero to h, r(0) = r, r(h) = 0.

r(y) = r - r/h y

area(y) = π (r - r/h y)^2 = π (r^2 - 2r^2y/h + r^2y^2/h^2) = π r^2(1-2y/h+y^2/h^2)

antiderivative area(y) = π r^2 (y-y^2/h+y^3/(3h^2))

integral 0 to h = π r^2(h-h^2/h+h^3/(3h^2) - (0)) = π r^2(h - h + h/3) = π r^2(h/3) = π/3 r^2 h

volume of this cone is π/3(4^2)18 cubic inches.

= 6 16 π = 96π cubic inches.

cone has twice the volume, 96/48.

cone height is 6 times the cylinder.

ratio of volume formula: π r^2 cancels.

cone over cylinder ratio is 6h/3 to h, 2 to 1.