If you learned about the 45-45-90 triangle (which is isosceles), then the faster way is to know that the hypotenuse (side opposite of right angle) is √2 times either one of the sides. 3√2 = (√2)x x = 3
But if you didn't learn the 45-45-90 triangle yet, that's ok. Recall the trigonometric ratios for right triangles: sine (sin), cosine (cos), tangent (tan).
If your angle is x, then sin(x) = opposite side / hypotenuse cos(x) = adjacent side / hypotenuse tan(x) = opposite side / adjacent side
Remember the hypotenuse is the side opposite and across from the right angle (3√2 in this case). An acronym to remember this is SohCahToa.
In this problem, the angle given is 45°, and you need to find the length of the adjacent side x. The hypotenuse is also given as 3√2.
Because we have the adjacent side and the hypotenuse, we use cosine to relate those two sides cos(45°) = x / (3√2) x = (3√2)cos45° If you plug this into your calculator (in degree mode), then x = 3
To find the percentage of cookies baked by Jenny we first have to know how many cookies total there were. 15+18+17=50 cookies all together. The question is asking us "what percentage" (x) "of" (multiply) 50 "is" (equals) 15? Using the variables and numbers only our questiion becomes 50x = 15. Divide both sides by 50 to get x = .3. Since this value is a percentage, we find that percentage by multiplying by 100. 30%.