Answer:
1)commutative property of addition
2)commutative property of addition
3)B
using the law of cosines:
a^2 = b^2 + c^2 - 2*b*c*cos(A)
a = 90, b = 55, c = 50
90^2 = 55^2 + 50^2 - 2*55*50*cos(A)
8100 = 3025 + 2500 - 5500 * cos(A)
5500 * cos(A) = 3025 + 2500 - 8100
5500 * cos(A) = -2575
cos(A) = -103/220
A = arccos(-103/220)
A = 117.9 degrees
Given:
Triangular garden
smallest side: x
medium side: x + 5ft
largest side: 2x - 6ft
Perimeter: 47 ft.
Perimeter = smallest side + medium side + largest side
47 ft = x + x + 5ft + 2x - 6ft
47 ft - 5ft + 6ft = 4x
48ft = 4x
48ft / 4 = 4x / 4
12 ft = x
smallest side: x = 12 feet
medium side: x + 5ft = 12ft + 5ft = 17 ft
largest side: 2x - 6ft = 2(12ft) - 6ft = 24ft - 6ft = 18ft
Perimeter: smallest + medium + largest
47ft = 12ft + 17ft + 18ft
47ft = 47ft
