Question

Solve the following simultaneous equations
a) 49x - 57y = 172; 57x - 49y = 252 (elimination method)
b) 3x + 2y = 29; 5 - y = 18 (substitution method)
c) 3x - y = 2; 2x - y = 3 (graphically)
d) y + 2x - 19 = 0; 2x - 3y + 3 = 0 (cramer's rule)

Answer 1

Answer:

Linear equations in two variables. If a, b, and r are real numbers (and if a and b are not both equal to 0) then ax+by = r is called a linear equation in two variables. (The “two variables” are the x and the y.) The numbers a and b are called the coefficients of the equation ax+by = r.

Answer 2

Step-by-step explanation:

According to the Question

Let the ratio be 5x : 4x

Total number of people in group = 72

We need to calculate the number of lawyers in the group & it is also given that the ratio of doctor to lawyers is 5:4

Sun of Ratios = Total number of people

Substitute the value we get

:\implies:⟹ 5x + 4x = 72

:\implies:⟹ 9x = 72

:\implies:⟹ x = 72/9

:\implies:⟹ x = 8

Now, putting the value of x = 8

4x = 4×8 = 32

Hence, the number of lawyers in the group is 32 .