Math help.. a few math problems i need help on please..?

Could anyone please help me with these math questions.. ??





1. Find the value of x. ?


Isosceles triangle A B and C are congruent to sides A B and B C. Angle A is 3x + 4 and angle B is 40.





A) 12


B) 22


C) 45.3


D) 70





2. Find the value of x?


A triangle with interior angles are 2x + 40, 4x + ^2, and 6x. The exterior angles are 6x and 6x^2.





A) 4


B) 5


C) 7


D) 10





3. Find the measure of x and y.


A triangle with interior angles X, 112, and 47. The exterior angle at 47 is y.





A)x=31, y=123


B)x=159, y=21


C)x=21, y=133


D)x=68, y=43

Math help.. a few math problems i need help on please..?
1. B) 22 degrees


3. C) x = 21; y = 133





1. Angle B is 40 degrees. Angle A and C, 140/2 which is 70 degrees. So, angle A equals to 70 degrees. 3x + 4. 70 degrees - 4 equals to 66 degrees. 66 degrees/3 = 22 degrees.





Angle A = (180 - 40)/ 2


= 140/2


= 70 degrees





3x + 4 = 70 degrees


3x = 70 - 4


= 66 degrees


x = 66/3


=22 degrees





2. I skipped that question because I have not learnt that yet.





3. Sum of angles in a triangle adds up to 180 degrees. One angle is 112 degrees, the other angle is 47 degrees, the last one would have to be 21 degrees. The exterior angle at 47 equals to sum of the other two angles in the triangle which does NOT include 47 degrees. 112 + 21 = 133 degrees. The other solution to find y would have to be angles on a straight line. 180 degrees - 47 degrees.





x = 180 - (112 + 47)


= 180 - 159


= 21 degrees





y = 112 + 21


= 133 degrees





OR





y = 180 - 47


=133 degrees.





Hope you understood.

geranium