Gregor is planting pea plants in his backyard. Some of the plants are tall and the rest are short. Some of the plants are yellow and the rest are green. The numbers of different plant types are in the ratio\[\text{Tall green}:\text{Tall yellow}:\text{Short green}:\text{Short yellow} = 8:5:2:1.\]If there are 1080 green plants, then how many total plants are in Gregor's yard?

1728.

Step-by-step explanation:

It is given that The numbers of different plant types are in the ratio  

Tall green:Tall yellow:Short green:Short yellow = 8:5:2:1.

Let the numbers of Tall green, Tall yellow, Short green:, Short yellow are 8x, 5x, 2x, x respectively.

Number of green plants

It is given that there are 1080 green plants.

Number of total plants

Therefore, total plants are in Gregor's yard is 1728.

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so:

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.