Find the value of x.

Mathematics

1 answer:

Travka [436]2 years ago

4 0

Answer:X=9

Step-by-step explanation:

x+18=3x

18=2x

x=9

Similar Triangles Question w/ Picture

melomori [17]

Answer:

$EF=\dfrac{120}{7}\ ft$

Step-by-step explanation:

Triangles CEF and CAD are similar right triangles (they have the common angle, so by AA postulate they are similar). Similar triangles have proportional corresponding sides, so

$\dfrac{EF}{AD}=\dfrac{CF}{CD}\\ \\\dfrac{EF}{40}=\dfrac{CF}{CD}$

Triangles DEF and DBC are similar right triangles (they have the common angle, so by AA postulate they are similar). Similar triangles have proportional corresponding sides, so

$\dfrac{EF}{BC}=\dfrac{DF}{DC}\\ \\\dfrac{EF}{30}=\dfrac{CD-CF}{CD}\\ \\\dfrac{EF}{30}=1-\dfrac{CF}{CD}$

Substitute the fraction $\frac{CF}{CD}$ from the first equality into the second equality:

$\dfrac{EF}{30}=1-\dfrac{EF}{40}\ [\text{Muliply by 120}]\\ \\4EF=120-3EF\\ \\4EF+3EF=120\\ \\7EF=120\\ \\EF=\dfrac{120}{7}=17\dfrac{1}{7}\ ft$

7 0

3 years ago

HELP PLEASE

zysi [14]

I just took the quiz so the answer's are...

The bowling alley charges $2 to rent shoes. Tom is going to rent shoes at the bowling alley. Therefore, Tom expects to spend $2 to rent shoes at the bowling alley.

Opposite sides of a rectangle are parallel. Side ABSide AB and side CDside CD are opposite sides of a rectangle. Therefore, side ABside AB and side CDside CD are parallel.

All four sides of a rhombus are the same length. Quadrilateral ABCDQuadrilateral ABCD is a rhombus. Therefore, all four sides of quadrilateral ABCDquadrilateral ABCD are the same length.

8 0

2 years ago

Read 2 more answers

Find the discriminant, and determine the number of real solutions. then solve x^2 +8x+20=0

vodomira [7]

Answer:

Part 1) The quadratic equation has zero real solutions

Part 2) The solutions are

$x_1=-4+2i$ and $x_2=-4-2i$