The negative 7 is the correct answer
Answer:
The magnitude of the resultant force is: 27.40 pounds
Step-by-step explanation:
Given



Required
The magnitude of the resultant vector
To do this, we apply cosine formula

This gives:




Take square roots of both sides


B is 5, you can solve this by first finding the value of a, which is 2, and then plug it into the other equation. 8+2=10 so we must also make the other side 10. We then do 10-5=5, 5 is the value of b
Answer:

Step-by-step explanation:
given
45 = 25m + b ( isolate the term in m by subtracting b from both sides )
45 - b = 25m ← divide both sides by 25
= m