2027 Shares

It seems an easy problem, but I don't know how to solve it.?

It seems an easy problem, but I don't know how to solve it.? Topic: It seems an easy problem, but I don't know how to solve it.?
June 16, 2019 / By Celeste
Question: In triangle ABC: AB=6 angle B=45degrees angle C=30 degrees therefore angle A=105degrees But how do I find the semi-perimeter [ (a+b+c)/2 ] ?
Best Answer

Best Answers: It seems an easy problem, but I don't know how to solve it.?

Annita Annita | 4 days ago
law of sines let a, and c, represent the lengths of the sides opposite the angles A, B , and C a / sin A = b / sin B = c / sin C and the reciprocals is true, too sin A / a = sin B / b = sin C /c AB = 6 is opposite angle C BC is opposite angle A AC is opposite angle B 6 / (sin 30º) = BC/ (sin (105º) = AC/sin (45º) 6/(1/2) = 12 12 = BC/sin (105º) = BC / (.9659) --> BC = 11.59 12 = AC/ sin (45º) = AC/ (√2/2) --> AC = 8.485 Now that you have the lengths, you can solve for the semiperimeter and I assume find the area of the triangle.
👍 236 | 👎 4
Did you like the answer? It seems an easy problem, but I don't know how to solve it.? Share with your friends
Annita Originally Answered: !?Can you solve this mathematics problem(it's an easy equation problem)?i need the ways of the solution too?
Well done to the first answer i'm pretty sure thats right. I've solved problems like this before and the hard bit is often not in solving equations, its about converting a real life problem into a mathematical problem. The confusing bit is deriving those two equations, but once you've got that sorted the rest is easy. Btw in case you don't have a fancy calculator handy: x² - 9x - 400 can be factorised as: (x-25)(x+16) giving x-25 = 0 x+16=0 x=25 x = -16 but we know the solution cannot be negative so only solution is x = 25 You can also complete the square: x² - 9x - 400 = 0 (x - 4.5)² - 20.25 - 400 = 0 (x- 4.5)² = 420.25 x - 4.5 = ±√420.25 x = 4.5 ± 20.5 x = 4.5 + 20.5 x = 4.5 - 20.5 x = 25 x = -16 so x must be 25 You can also use the quadratic formula: x = -b±√(b² - 4ac) /2a a=1 b=-9 c=-400 x = 9 ±√(81 +1600) /2 x = 9 ± 41 /2 x = 50/2 x = -32/2 x = 25 x = -16 nice to have options sometimes ;)
Annita Originally Answered: !?Can you solve this mathematics problem(it's an easy equation problem)?i need the ways of the solution too?
SOLUTION: Let 'y' be the total number of friends of Clara Number of pencils, 'x' = 400 Number of pencils for each friend of Clara, x = 400 / y ---> (1) Now, when 4 friends leave the group (means, y -4), then Each friend receives 5 more pencils (means, y - 4 = [x + 5] ----> (2) Substituting (1) in (2) => y - 4 = ( 400 / y ) + 5 => y -4 = [ 400 + 5y] / y => y (y - 4) = 400 + 5y => y^2 - 4y - 5y - 400 = 0 => y^2 - 9y - 400 = 0 taking factor => (y + 16) (y - 25) = 0 y - 25 = 0 => y = 25 Note: y + 16 = 0 will give 'y' as - 16, hence omitted.

Yahweh Yahweh
b / sin 45° = 6 / sin 30° b = 6 sin 45° / sin 30° b = 6√2 a / sin 105° = 6 / sin 30° a = 6 sin 105 ° / sin 30° a = 3√6 + 3√2 P = 6 + 6√2 + 3√6 + 3√2 P = 6 + 3√6 + 9√2 P/2 = 3 + ( 3√6 + 9√2 ) / 2
👍 100 | 👎 -3

Sheldon Sheldon
I am assuming AB is opposite angle C use sine formula 6/sinC = BC/sineA BC = 6sinA/sinC = 11.59.............correct to 2 decimal places AC/sinB = 6/sinC AC = 8.49..........................correct to 2 decimal places a + b + c = 26,08 Semiperimeter = 13.04
👍 97 | 👎 -10

Sheldon Originally Answered: Solve this math problem? It's easy?
Alright. 6x^3*7x^2-(4x^3)^2+(-3x^3)^2-(-4x^2)(5x^... right? (42x^5) - (16x^6) + (9x^9) - (-20x^5) - (10x^5) + (17x^6) (52x^5) - (x^6) + (9x^9) 9x^9 - x^6 + 52x^5 I think that is right.

If you have your own answer to the question It seems an easy problem, but I don't know how to solve it.?, then you can write your own version, using the form below for an extended answer.