Answer:
x = 4/5
Step-by-step explanation:
Subtract 3/x+4, then multiply by x/5:
![\dfrac{3}{x}+9=\dfrac{7}{x}+4\\\\5=\dfrac{4}{x}\\\\\boxed{x=\dfrac{4}{5}}](https://tex.z-dn.net/?f=%5Cdfrac%7B3%7D%7Bx%7D%2B9%3D%5Cdfrac%7B7%7D%7Bx%7D%2B4%5C%5C%5C%5C5%3D%5Cdfrac%7B4%7D%7Bx%7D%5C%5C%5C%5C%5Cboxed%7Bx%3D%5Cdfrac%7B4%7D%7B5%7D%7D)
_____
If you meant 3/(x+9) = 7/(x+4), you need to write it with parentheses around the denominator. (In that case, x=-12.75.)
Answer:
x = 45
x = 19
Step-by-step explanation:
A straight line = 180°
So,
12.
3x + x = 180
4x = 180
---- -----
4 4
x = 45
13.
(5x + 4) + (x - 2) + (3x + 7) = 180
Combine like terms:
(5x + 4) + (x - 2) + (3x + 7) = 180
9x + 4 - 2 + 7 = 180
9x + 9 = 180
-9 -9
------------------
9x = 171
----- -----
9 9
x = 19
Hope this helped.
Answer:
s = 16.97 units
Step-by-step explanation:
Since this is a right triangle, we can use trigonometry to figure out the lengths of the sides.
Look at the 45 degree angle. We can use the opposite side (12) and the hypotenuse (s) to solve for s.
Opposite and hypotenuse is sine, so we are using sine. The sine of 45 degrees is 0.70710678118. Make an equation like so:
- 0.70710678118 =
, and we are solving for s.
Put a 1 in the denominator of sine(45 degrees) so you can cross-multiply.
Cross multiply.
Divide both sides by sine(45 degrees).
The length of side s is 16.97 units.
Another way to have done this problem is to use the Pythagorean theorem: a^2 + b^2 = c^2
Substitute 12 for a and b and solve for c, the hypotenuse.
Evaluate the exponents.
Add them together.
Square root 288 to solve for c.
c = 16.97, which is the same answer as you got using trigonometry.
Answer:
y = 1/3mx + b
Step-by-step explanation:
x = 3(y - b)/m
~Multiply m to both sides
mx = -3b + 3y
~Add 3b to both sides
mx + 3b = 3y
~Divide everything by 3
1/3mx + b = y
y = 1/3mx + b
Best of Luck!