Answer:

Step-by-step explanation:
<u>Use the Pythagorean Theorem</u>
The equation for the Pythagorean Theorem is 
* a and b are the lengths of the legs, and c is the hypotenuse.*
(To know which side is the hypotenuse look at longest side which is across the right angle).
a= x, b=8, c=9

Let's Plug in the side lengths:

Evaluate 8^2 and 9^2:

Subtract 64 from both sides:


Take the square root of both sides:

___________________________
2(5*10)+2(10*4)+2(5*4)=
2(50)+2(40)+2(20)=100+80+40=
220 cm^2
I found the answer by finding the areas of the 3 different sides, multiplying each area by 2 since each side has another side that is equal on a rectangular prism, then adding all of them together.
We have two unknowns: x and y. Now, we have to formulate 2 equations. The first would come from the use of the given ratio:
We use the distance formula to find the distance between coordinates:
3/4 = √[(x-4)²+(y-1)²] / √[(4-12)²+(1-5)²]
√[(x-4)²+(y-1)²] = 3√5
(x-4)²+(y-1)² = 45
x² - 8x + 16 + y² - 2y + 1 = 45
x² - 8x + y² - 2y = 28 --> eqn 1
The second equation must come from the equation of a line:
y = mx +b
m = (5-1)/(12-4) = 1/2
Substitute y=5 and x=12 for point (12,5)
5 = (1/2)(12) + b
b = -1
So, the second equation is
y = 1/2x -1 or x = 2 + 2y --> eqn 2
Solving the equations simultaneously:
(2 + 2y)² - 8(2 + 2y) + y² - 2y = 28
Solving for y,
y = -2
x = 2+2(-2) = -2
Therefore, the coordinates of point A is (-2,-2).
Answer:
a = -10
Step-by-step explanation:
Multiply first example by 3 and subtract by second example, you will get the following:
3*(5x + 2y) = 3*22 => 3*5x + 3*2y = 66 => 15x + 6y = 66
now subtraction:
(15x + 6y) - (-2x + 6y) = 66 - 3
15x + 6y + 2x - 6y = 63
15x + 2x + 6y - 6y = 63
17x = 63
x = 63/17 ≈ 3.705..... and as it says to round to the nearest tenth our answer would be: x = 3.7