7x - y= -5. Standard form is when it is written with x and y on the same side, but x is not negative or a fraction. To find the slope and y intercept, you must change the first two equations to slope intercept. You get y=7x-5 for the first one and y=11/3x+5 for the seccond equation. Take the 5 as your y intercept and the 7 as your slope and you get y=7x+5. Now you need to change it into standard form. When all is said and done, your final answer should be 7x - y = -5.
Hello again! So we will be using the pythagorean theorem (

) to solve for the bottom leg of the triangles. After we do that, we'll subtract the value of the legs from 31, and that'll be x.
Plug in 17 and z (or any variable that isn't x) into the leg variable and 19 into the hypotenuse variable, and from there we can solve.

Solve the exponents to get

Subtract 289 on each side to get

Lastly, square root each side of the equation and your answer should be

(To get more accurate answers, you shouldn't round until the end of the problem)
Nextly, we will need to subtract

from 31. And since there are 2 triangles, you'll need to multiply

by 2.
In short, x = 14.0
Perimeter of the arc = 1/2 πD
Perimeter of the arc = 1/2 x π x (16 x 2)
Perimeter of the arc = 50.27mm (Nearest hundredth)
Perimeter of the figure = 50.27 + 20 + 20 = 90.27mm
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Answer: Perimeter = 90.27 mm
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