Question

(3) Solve the following sets of simultaneous equations.
(i) x + y = 4; 2x - 5y = 1
​

Answer 1

Answer:

(1,3)

Step-by-step explanation:

x+y=4-----------EQ.1

2x-5y=1--------------EQ.2

Now,we multiply EQ.1 with 2

So, 2(x+y=4)

= 2x+2y=8---------------EQ.3

Now,

2x+2y=8

2x-5y=1

- + -

_________

7y=7

y=7/7

y=1

put y=1 in EQ.1

x+1=4

x=4-1

x=3

so,(x,y)=(1,3)

Answer 2

Answer:

${ \red{x + y = 4 - - - - - (1)}}$

${ \red{2x - 5 y = 4 - - - - - (2)}}$

${ \pink{multiply \: eq.(1) \: by \: (2)}}$

${ \red{2x + 2y = 8 }} \\ { \red{2x - 5y = 8 }} \\ { \underline{ \red{ - \: \: \: \: + \: \: \: \: \: - }}}$

${ \red{ 7y = 7 }}$

${\huge{\boxed{ \red{ y = 1 }}}}$

${ \red{ x + y = 4 }}$

${ \red{ x + 1= 4}}$

${ \huge{ \boxed{ \red{ x = 3}} }}$

Step-by-step explanation:

Hope this helps you ✌️