Question

[7,8] is the difference between

2 vectors with components [a, 5] and

(-4,-3). What is a

Answer 1

The value of
`a` is 3.

Explanation:

Let be
`\vec a = \langle a, 5 \rangle` and
`\vec b = \langle -4,-3 \rangle`, the difference between the two vectors is:

`\vec c = \vec b - \vec a`

`\vec c = \langle a, 5\rangle - \langle -4,-3 \rangle`

`\vec c = \langle a+4,8 \rangle`

If we know that
`\vec c = \langle 7,8 \rangle`, the value of
`a` is:

`\langle 7, 8 \rangle = \langle a+4, 8\rangle`

In which,

`a + 4 = 7`

`a = 3`

The value of
`a` is 3.