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4 years ago

Please show your work

Mathematics

2 answers:

maw [93]4 years ago

7 0

1. 1st number be x, 2nd number be y

Adding 5 times the first number and 8 times the second number gives a total of -13

so 5x+8y=-13

Adding 5 times the first number and 10 times the second number gives -15

so 5x+10y=-15

subtracting the above two eqns

(5x+8y)-(5x+10y) = -13-(-15)

-2y=2

y=-1

put back in first eqn 5x+8(-1)=-13

5x=-5

x=-1

2. area of town A = 1500

every year, the area of the town decreases by 7%

so after 1 year, A=1500*(1-7%)=1500*(0.93)

after x years, A=1500(0.93)^x

STALIN [3.7K]4 years ago

6 0

Answer:

Step-by-step explanation:

1. Subtract "Adding 5 times the first number and 8 times the second number gives a total of -13"

from "Also, adding 5 times the first number and 10 times the second number gives -15"

10 -8 = 2 times the second number gives -15 - (-13) = -2

the second number = -1

Put that in "adding 5 times the first number and 10 times the second number gives -15":

5 times the first number + 10(-1) = -15

5 times the first number = -5

the first number = -1

2. Given area of town A is currently 1500 and after every year, the area of the town decreases by 7%.

After 1 year. new area = 1500 * (1-7%)

After 2 years, new new area = 1500 * (1-7%) * (1-7%)

1 - 7% = 1 - 0.07 = 0.93

So the exponential function that represents the situation is 1500 * 0.93^(number of years)

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