Option A is correct
assuming we use the Pythagorean theorem whose formula is c²= √a² + b²
C being the longest side, a=15 and b=20
c² = √15²+ 20²
c² = √625
c= 25
if you try this formula with the other options it shows it's not a right triangle
Answer:
D. -1
Step-by-step explanation:
w^2+3w-11, w=-5
(-5)^2 + 3*(-5) - 11
= 25 - 15 - 11
= 25 - 26
= -1
Area of the rectangle = x^2 + 8x + 15 square units
Explanation:
Length = x + 5
Breadth = x + 3
Area = l x b = (x + 5)(x + 3) = x(x + 3) + 5(x + 3) = x^2 + 3x + 5x + 15 = x^2 + 8x + 15 square units
Answer:
Step-by-step explanation:
Now we know that
sec²θ -tan² θ= 1 ,
So tan²θ =sec²θ - 1
So the left of the given equation will be
sec²20 + sec²40 +sec²80 - 3
So
1/cos²20+1/cos²49+1/cos²80 -3
Remember sec θ= 1/cosθ
So
= since secθ = 1/cosθ
we have
= 1.1324 + 1.7040 + 33.1634 - 3
= 35.9998 - 3
= 33
