Please help me with this with steps

(x - y) = 9

Step-by-step explanation:

**Note: we cannot use similar triangle proportionality, as ΔABC is NOT a right triangle**

Using Pythagoras' Theorem a² + b² = c²

(where a and b are the legs and c is the hypotenuse of a right triangle)

Create equations for both smaller interior right triangles using Pythagoras' Theorem:

Larger right triangle

   CD² + x² = 17²

⇒ CD² = 17² - x²

Smaller right triangle

   CD² + y² = 10²

⇒ CD² = 10² - y²

Equate equations:

        CD² = CD²

⇒ 17² - x² = 10² - y²

Given:

AB = 21  and AB = x + y

⇒ x + y = 21

⇒ y = 21 - x

Substitute  y = 21 - x  into  17² - x² = 10² - y²  and solve for x:

⇒ 17² - x² = 10² - (21 - x)²

⇒ 17² - x² = 10² - (441 - 42x + x²)

⇒ 17² - x² = 10² - 441 + 42x - x²

⇒ 289 = 100 - 441 + 42x

⇒ 630 = 42x

⇒ x = 630 ÷ 42

⇒ x = 15

Substitute found value for x into  y = 21 - x and solve for y:

⇒ y = 21 - 15 = 6

Finally, substitute found values for x and y into (x - y):

⇒ x - y = 15 - 6 = 9

question: match the eqaution with its graph -8x - 5y = 40

answer: 8 x 5 = 40

x= absiss

y= orderly

so you have a proportional graph

question answered by

(jacemorris04)