Answer:
4 and 5
Step-by-step explanation:
xy = 20
x = 2y - 3
(2y-3)y = 20
2y^2 - 3y = 20
2y^2 - 3y - 20 = 0
Solve the quadratic equation
you get y = 4, -5/2
Use 5 since it is one of the options
xy = 20, y = 4
x = 5
Here you have to find which each variable is, for this you start of picking one equation,
x + 2y + 6z = 4
-3x + 2y - 2 = -4
4x + 2z = 16
depending the equation you pick you multiply that by a certain number that will give you the opposite of one of the other equations,
-1(x + 2y + 6z = 4)
= -x -2y - 6z = -4
With this you add or subtract it with the equation that has the same number or variable, or both,
In this case it will be the equation,
-3x + 2y + 6z = 4
You can use this one or the third equation since both have a positive 2y which will cancel with -2y from the new equation,
-x - 2y - 6z = -4
-3x + 2y -z = -4
= -4x -7z = -8
Now you since you just eliminated the variable (y) you now have 2 variables, and the last equation has only 2 variables, meaning now you find the answer to those to equations,
-4x -7z = -8
4x + 2z = 16
= -5z = 8
Now leave the variable by itself,
z = 8/5
Now you found the variable (z), with this just substitute on one of the equations we used to find (z) so you can find (x), after that substitute those answered to on of the original equations so you can find (y)
Answer:
The answer is A) 1.
Step-by-step explanation: They only cross once
<span>Diagonals of a rhombus are perpendicular and bisect each other. This means this rhombus is composed of four right triangles with legs of length 6 cm and 8 cm, with their hypotenuses forming the perimeter of the rhombus. The Pythagorean theorem a^2+ b^2 = c^2 can be used to find the length of the hypotenuse. 6^2+8^2 = 36+64 = 100. The square root of 100 is 10, so the length of a side of the rhombus is 10 cm.</span>