<h3 /><h3>

</h3>
This is the formula for circumference of circle
Use the trick x+ y+ z =0 and 6+8+z=0,...so z= -14
The circle goes thru the given points <span>(3,-4) And (3,5). Since the x-coordinate does not change, the diameter lies right on the vertical line x=3. Since the vertical distance between these points is 5-(-4), or 9, the radius is 9/2.
The standard eq'n of a circle is (x-h)^2 + (y-k)^2 = r^2
Let's subst. what we know: we get (x-3)^2 + (y-1/2)^2 = (9/2)^2. Note that y = 1/2 is halfway between y=-4 and y=5.</span>
This means that the bicycle was discounted in total by 60%, so $315 is 40% of the original price to get 40% to 100% youd multiply it by 2.5 so so the same to the price 315 x 2.5= 787.5
In 8, 9, 10, all the triangles are similar, meaning corresponding sides have the same ratio.
8. hypotenuse / (short side) = 25/x = x/9
x² = 25*9 = 5²×3²
x = √(5²×3²) = 5*3 = 15
9. (long side) / (short side) = x/7 = 9/x
x² = 7*9
x = √(9*7) = 3√7
10. (short side) / (long side) = x/48 = 48/64
x = 48²/64 = 36