There's 60 min, so 1/8 of 60
60/8= 7.5 minutes in 1/8 of 60
Well the equation is (A^2)+(B^2)=(C^2)
A= x
B= 2x
C will always be the longest side because it is the Hypotenuse = 25
So if you plug in those numbers into the equation...
(x^2) + (2x^2) = (25^2)
x^2 + 4x^2 = 625
Combine like terms
5x^2 = 625
Divide by five to both sides
x^2 = 125
Then Square root,
x = sqrt(125)
x = sqrt(25* 5)
x = 5sqrt(5)
X=Marks sister's age
x+11= Marks age
x+11 +8 = 2x+8
x+19=2x +8
x+19-x=2x-x +8
19-8=x+8-8
11=x Marks sisters age in 8 years
11-8= 3 Marks sisters age now
x+11=22 Marks age in 8 years
22-8= 14 Marks age now
Answer:
x = 1
y = -3
Step-by-step explanation:
cos(pi) = -1
so many ways :
sqrt(0.5/2) = sqrt(0.5/2 × 8/8) = sqrt(4/16)
= sqrt(0.5/2 × 18/18) = sqrt(9/36)
= sqrt(1/4) = 1/2
"nicest" approach (all integers) :
3x² = sqrt(9)
3x² = 3
x² = 3/3 = 1
x = 1
2y = sqrt(36)
2y = 6
y = 6/2 = 3
one of them has to be negative (because cos(pi) = -1), so it has to be y, because 3x² cannot be negative with real numbers.
so, y = -3
-1 × 3×1²/(2×-3) = sqrt(0.5/2) = 1/2
-1 × 3/-6 = 1/2
3/6 = 1/2
1/2 = 1/2
correct
