The equation y=1.2x+8.9 is a linear model for data comparing the ages of babies between 1 and 11 months old (x) and their average weights in pounds (y). about how much weight does a baby gain per month?

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For babies between 1 and 11 months old, the equation y = 1.2x + 8.9 models the baby's weight when the baby is x months old.  A baby in that age range weighs 17.5 lbs.  What is the best estimate for the age of the baby?

7 months

Step-by-step explanation:

1.2 * 7 + 8.9 = 17.3 & 17.3 is close to 17.5

I just took the test!

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions