7.) Зу = 2-х
2y + 10 = 6x

By cross multiplication method

x=

(a

1

b

2

−a

2

b

1

)

(b

1

c

2

−b

2

c

1

)

&

y=

(a

1

b

2

−a

2

b

1

)

(c

1

a

2

−c

2

a

1

)

Where a

1

x+b

1

y+c

1

=0 & a

2

x+b

2

y+c

2

=0

are 2 lines

⇒x=

2(−2)−(3×3)

3(−6)−(−2)(−17)

=

−13

−52

=4

y=

2(−2)−(3×3)

(−17)3−(−6)2

=

−13

−39

=3

⇒

x=4&y=3

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions

£56

step-by-step explanation: