What is the justification for the step taken from line 2 to line 3?

5 lines of math. the first line has, 3 x plus 9 minus 7 x equals x plus 10 plus x. the second line has, negative 4 x plus 9 equals 2 x plus 10. an arrow pointing from the front of the second line to the front of the third line. the third line has, negative 6 x plus 9 equals 10. the fourth line has, negative 6 x equals 1. the last line has x equals negative startfraction 1 over 6 endfraction.

the subtraction property of equality
the multiplication property of equality
combining like terms on one side of the equation
the distributive property

50 points! antonio made a scale model of a building. the model's scale is 1 inch to 235 feet and its height is 3.5 inches. what is the exact height of the actual building? enter your answer in the box.

Which statements regarding the diagram are true? check all that apply.

Browning labs is testing a new growth inhibitor for a certain type of bacteria. the bacteria naturally grows exponentially each hour at a rate of 6.2%. the researchers know that the inhibitor will make the growth rate of the bacteria less than or equal to its natural growth rate. the sample currently contains 100 bacteria. the container holding the sample can hold only 300 bacteria, after which the sample will no longer grow. however, the researchers are increasing the size of the container at a constant rate allowing the container to hold 100 more bacteria each hour. they would like to determine the possible number of bacteria in the container over time. create a system of inequalities to model the situation above, and use it to determine how many of the solutions are viable.