Q1. Form the pair of linear equations in the following problems, and find their solutions graphically.
10 students of Class X took part in a Mathematics quiz. If the number of girls is 4 more than the number of boys, find the number of boys and girls who took part in the quiz.
Let the number of boys be x and the number of girls be y.
Now, According to the question,
Total number of students in the class = 10, i.e.
And the number of girls is 4 more than the number of boys,i.e.
Different points (x, y) for equation (1)
X | 5 | 6 | 4 |
Y | 5 | 4 | 6 |
Different points (x,y) satisfying (2)
X | 5 | 6 | 7 |
y | 1 | 2 | 3 |
Graph,
As we can see from the graph, both lines intersect at the point (7,3). that is x= 7 and y = 3 which means the number of boys in the class is 7 and the number of girls in the class is 3.