Adding and subtracting the given polynomials

You have to combine like terms, so the variable (x, y, s, d, c) and the exponents must be the same in order to combine them.

For example:

x² + x³    Since they don't have the same exponent, you can't combine them

y² + 3y² = 4y²

23x + x = 24x

4. 2s² + 1 + s² - 2s + 1    You can rearrange it if it makes it easier

2s² + s² - 2s + 1 + 1 = 3s² - 2s + 2

5. 5t² - 2t - 1 - (3t² - 5t + 7) Distribute/multiply the - to (3t² - 5t + 7)

5t² - 2t - 1 - 3t² + 5t - 7 = 2t² + 3t - 8

Do the same for #9 and #10, and you should get:

9. 2k² + 5k - 9

10. 6y³ - 7y² - 6y - 12

d) by the cross product property, ab^2 = bc multiplied by ad

step-by-step explanation:

we are given

in the given triangle abc

angle a is 90° and segment ad is perpendicular to segment bc

we can see that

triangle(abc) and triangle(abd) are similar because they have common side and same angle (90 degree)

so, triangles(abc) and abd are similar

since, they are similar

so, the ratio of their sides must be equal

we get

now, we can cross multiply

and we get

so, this could be step to prove it