Answer:
No mistake
Step-by-step explanation:
2x + y = 5
x - 2y = 10
y = 5 - 2x
x - 2(5 - 2x) = 10
x - 10 + 4x = 10
5x - 10 = 10
5x = 20
x = 4
2(4) + y = 5
y = -3
She made no mistake
You can check by plugging in x = 4 and y = -3 into the original equations . They fit exactly.
Answer:
85.1 ft
Step-by-step explanation:
The extreme water slide forms a 20 angle with the tower it leans against 80 feet above the ground find the length of the slide x
We solve using the Trigonometric function of Cosine
cos y = adjacent/hypotenuse
y = angle = 20°
Adjacent = 80 ft
Hypotenuse = ?
cos 20 = 80/Hypotenuse
Hypotenuse = 80/cos 20
x = 85.134221798 ft
Approximately = 85.1 ft
Length of the slide = 85.1 ft
Answer:
25/13
Step-by-step explanation:
Answer:
3 triangles
Step-by-step explanation:
Perimeter of triangle = a + b + c
Given that :
P = 12
and a, b, c are natural numbers
Let :
Side A = a
Side B = b
Side C = 12 - (a + b)
Side A + side B > side C - - - (condition 1)
a + b > 12 - (a + b)
a + b > 12 - a - b
a + a + b + b > 12
2a + 2b > 12
2(a + b) > 12
a + b > 6
Side A - side B < side C
a - b < 12 - (a + b)
a - b + a + b < 12
2a < 12
a < 6
b < 6 (arbitrary point)
Going by the Constraint above :
The only three possibilities are :
(2, 5, 5)
(3, 4, 5)
(4, 4, 4)
Total number of triangle = 3
Equilateral triangle (all 3 sides equal) = (4, 4, 4) = 1
Isosceles triangle (only 2 sides equal) = (2, 5, 5) = 1