a helicopter is bought for 5 million. its value depreciated by 7%each year .how many years wil it take for value to halve​

Number of year = 9.5 year

Step-by-step explanation:

Given:

Initial value[Cost price] = $5,000,000

Depreciation rate[r] = 7% = 0.07

Final value[After depreciation cost] = 5,000,000 / 2 = $2,500,000

Find:

Number of year[After half value]

Computation:

A = p[1-R]ⁿ

Final value = Initial value[1-r]ⁿ

2,500,000 = 5,000,000[1-0.07]ⁿ

0.5 = [0.93]ⁿ

Number of year = 9.5 year

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18