Is $a\left(2x+3\right)=9x+15+x$ an identity

Aline has a slope of and a y-intercept of –2. what is the x-intercept of the line?

True or false: the graph of y=f(bx) is a horizontal compression of the graph y=f(x) if b< 1

Scores on the cognitive scale of the bayley-scales of infant and toddler development range from 1 to 19, with a standard deviation of 3. calculate the margin of error in estimating the true mean cognitive scale score, with 99% confidence, if there are 12 infants and toddlers in a sample.