For the equation of the line of the form y = mx + b, m is the slope of the line and b is the y-intercept which is the value of y when x is equal to zero. The slope is the rate of change of y per change in x. "y" would represent the dependent variable which is the weight of the baby while "x" represents the independent variable which is the number of months or the age of the baby in months. We calculate the slope as follows:
slope = (11 - 9) / ( 4 - 0) = 2/4 = 0.5
at x = 0, it is said that the weight of the baby is 9 lbs so the value of b would be 9.
The equation of the line would be y = 0.5x + 9
Answer:
x = 27
Step-by-step explanation:
ΔBRD and ΔQCD are similar, hence the ratios of corresponding sides are equal, that is
= 
note that BD = 26 + 39 = 65
substitute values into the ratio equation
= 
( cross- multiply )
65x = 39(x + 18)
65x = 39x + 702 ( subtract 39x from both sides )
26x = 702 ( divide both sides by 26 )
x = 27
