Join the centre O to the chord (let it be MN) & let OH be the perpendicular to the chord
OH bisects MN into 2 equal parts (each one is x/2)
OMH is a right triangle with one side =8, the second leg =x/2 & the hypotenuse = 12 (Radius)
Apply Pythagoras:
12² = 8² +(x/2)² ==>144=64 + x²/4 ==> x²=4(144-64) =320
x²=320==> x=√320 =17.88 ≈17.9
Answer:
V ≈ 527.79
Step-by-step explanation:
Formula is V= πr2h
therefore
V = π * 4 * 2 * 10.5
V = π * 8 * 10.5
V ≈ 527.79
Lila did it correctly. The answer is 324
Following PEMDAS, we first focus on the parenthesis. So we simplify 9-3 to get 6
So we go from
18*4^2+(9-3)^2
to
18*4^2+6^2
The next step is applying exponents. In this case, squaring the terms, so we go from
18*4^2+6^2
to
18*16+36
Next is multiplying
18*16+36
turns into
288+36
Finally, add up 288 and 36 to get 288+36 = 324
That confirms that Lila is correct
----------------------
The error that Rob made is that he computed 18*4^2+9^2-3^2 but it is NOT correct. Saying (x-y)^2 = x^2-y^2 isn't a true equation for all x and y. Again you have to simplify what is in the parenthesis first, and then you can square it. Or you must use the FOIL rule to expand out (9-3)^2
Answer:
159.8195397043133
Step-by-step explanation:
2²⁰
------------------ = 159.8195397043133
3⁸