mark must leave it for 5.5 months or 5 and half moths to gain 5600 in interest .
<u>Step-by-step explanation:</u>
Here we have , mark invests 8000 in an account that pays 12% interest and 2000 in one that pays 8%. if he leaves the money in the accounts for the same length of time, We need to find how long must he leave it to gain 5600 in interest . Let's find out:
Let mark invests 8000 in an account that pays 12% interest and 2000 in one that pays 8% for time x months , So total interest gain is 5600 i.e.
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Therefore , mark must leave it for 5.5 months or 5 and half moths to gain 5600 in interest .
Step-by-step explanation:
x=width of pool
2x=length of pool
the dimensions of the rectangle forming the walkway and the pool are x+4 and 2x+4
the area of this rectangle minus the area of the pool is 196 square feet
(2x+4)(x+4)-(x)(2x)=196
2x^2+4x+8x+16-2x^2=196
combine similar terms
12x+16=196
12x=196-16
12x=180
x=180/12
x=15 feet is the width of the pool
check: 34*19-30*15=196
646-450=196
196=196
Can you show us the number line model?