Question

How do u solve these two equations ??

a + 2b = 4
3a + b = 7

Answer 1

• a = 2
• b = 1

Explanation:

We know that:

• a + 2b = 4
• 3a + b = 7

Work:

• a + 2b = 4

3a + b = 7

• 3(a + 2b = 4)

3a + b = 7

• 3(a + 2b = 4)
• 3a + b = 7

• 3a + 6b = 12
• 3a + b = 7

• 3a + 6b = 12
• -3a - b = -7

• 5b = 5
• b = 1

Now, let's substitute the value of b into the first equation.

• a + 2b = 4
• => a + 2(1) = 4
• => a + 2 = 4
• => a = 2

Hence, the missing values are:

• a = 2
• b = 1

Answer 2

Explanation:

a + 2b = 4

3a + 6b = 12

3a + b = 7

5b = 5

b = 1

a = 2 because

2(1) + a = 4