The magnitude and direction of two forces acting on an object are 100100 pounds, s7878degrees°e, and 5050 pounds, n5353degrees°e, respectively. find the magnitude, to the nearest hundredth of a pound, and the direction angle, to the nearest tenth of a degree, of the resultant force.

  138.06 lb N86.1°E

Step-by-step explanation:

There are several ways you can work this. One of the most straightforward is to resolve each vector into its north and east components, add those, and then covert the result back to magnitude and direction.

A diagram can help immensely.

We note that S78°E is the same as E12°S. Since we're used to seeing the coordinate system with the +x axis aligned with east, it can be convenient to think of the first force as 100 lb at -12°.

The angle of the second force is N53°E, which can be expressed as E37°N. Then in x-y coordinates, this force is 50 lb at +37°.

The components of the sum are the sum of the components:

  R = F1 +F2 = (100cos(-12°) +50cos(37°), 100sin(-12°) +50sin(37°))

  = (137.747, 9.300)

The the magnitude of the resultant is computed using the Pythagorean theorem:

  ||R|| = √(137.747² +9.300²) ≈ 138.06

and the angle is computed using the arctangent function. Here, our diagram tells us the angle is in the first quadrant, so is positive (relative to +x, or East).

  ∠R = arctan(9.300/137.747) ≈ 3.9°

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We want to express the answer in terms similar to the way the given forces are expressed, so we want the angle relative to north. The resultant is then described by ...

  R = 138.06 lb at N86.1°E

isocolese triangle

we know that the line connect a and b is the hyptonuse

so first find the hypotonuse length using the distance formula, call the length c

since it is an isocolese triangle, the lengths of the legs are the same

using pythagorean theorem,

in this case, a=b since isocolese triangle so we get

or

we can find c so we can find the distances

we know that if we draw 2 circles, each has center at a and b, and find where they intersect, we can the 2 possible locations for c

if a has center at (xa,ya) and b has center at (xb,yb), then we can solve where

and

intersect to find where they intersect

i'm not going to put an example because i have to go to class. i hope this explanation is enough