Answer:
x= -1, y=1
Step-by-step explanation:
First label the 2 equations.
7x +6y= -1 -----(1)
-x +2y= 3 -----(2)
Then choose which term you would like to eliminate. To eliminate the y term, multiply equation (2) by 3 such that the coefficient of y is 6.
(2) ×3:
-3x +6y= 9 -----(3)
Since the coefficient of y is positive 6 in both equations, subtract one equation from the other.
(3) -(1):
-3x +6y -(7x +6y)= 9 -(-1)
Expand:
-3x +6y -7x -6y= 9 +1
-10x= 10
x= 10 ÷(-10)
x= -1
Substitute x= -1 into (2):
-(-1) +2y= 3
1 +2y= 3
2y= 3 -1
2y= 2
y= 2 ÷2
y= 1
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2nd method: eliminating the x term
(2) ×7:
-7x +14y= 21 -----(3)
Since the coefficient of y in equation (1) is a positive 7, while that in equation (3) is a negative 7, add the 2 equations together to eliminate the x term.
(1) +(3):
7x +6y -7x +14y= -1 +21
20y= 20
y= 20 ÷20
y= 1
Substitute y= 1 into (2):
-x +2(1)= 3
-x +2= 3
-x= 3 -2
-x= 1
x= -1
Answer:
∠BEC=90°
Step-by-step explanation:
∠A=∠BCD and ∠ABC=∠D because opposite angles in a parallelogram are equal.
∠A=∠BCD=70
All angles in a quadrilateral add to 360:
∠A+∠ABC+∠BCD+∠D=360
∠ABC+∠D=360-140=220
∠ABC=∠D=110
Since ∠ABC=∠ABE+∠EBC, and ∠ABE=∠EBC (because BE is an angle bisector), ∠EBC=55.
Since ∠BCD=∠BCE+∠ECD, and ∠BCE=∠ECD (because CE is angle bisector), ∠BCE=35.
All angles in a triangle add to 180:
∠BCE+∠EBC+∠BEC=180
35+55+∠BEC=180
∠BEC=180-90
∠BEC=90°
I think rational or it might be irrational but I think it’s rational
The statement at the top says that the triangles are 'similar'. That means that the corresponding angles are equal, and each pair of corresponding sides have the same ratio. From the 4 and the 8, you can see that each side in the small one is 1/2 the length of the corresponding side in the big one. So the missing sides are 1/2 the length of the 7 and the 12.
Answer:
46.94 degrees (approx)
Step-by-step explanation:
