For what value of b the graphs of the functions y = 3x + b and y = 2x + 4 intersect

| September 10, 2021 | education

For what value of b the graphs of the functions y = 3x + b and y = 2x + 4 intersect at the point that lies on the abscissa axis.

We are given two equations of the straight lines y = 3x + b and y = 2x + 4. We need to find the value of the variable b at which the straight lines intersect at a point lying on the abscissa axis.

So, we will find the coordinates of the point, the intersection of the graph of the function y = 2x + 4 with the abscissa axis, that is, we will solve the equation at y = 0.

0 = 2x + 4;

– 2x = 4;

x = 4 / – 2;

x = – 2.

So, the graph of the function y = 2x + 4 intersects the abscissa at a point with coordinates (- 2; 0).

Substitute the coordinates of the found point into the equation of the straight line y = 3x + b and find the value of the unknown b:

0 = 3 * (- 2) + b;

6 = b;

b = 6.

Answer: for b = 6.



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.