Answer:
D = 120° , E = 30° , F = 30°
Step-by-step explanation:
Let D = 4x
Let E&F = x
4x + x + × = 180°[angles in triangle is 180°]
6x = 180°
x = 180/6
x = 30°
E = 30°
F =30°
D =4(30°)
=120°
(Correct me if i am wrong)
The right answer is Option A.
Step-by-step explanation:
Let,
x be the postcards
y be the large envelops
According to given statement;
14x+5y=12 Eqn 1
10x+15y=24.80 Eqn 2
Multiplying Eqn 1 by 3;

Subtracting Eqn 2 from Eqn 3;

Dividing both sides by 32

Putting x=0.35 in Eqn 1;

Dividing both sides by 5

Therefore, one large envelope costs $1.42
The right answer is Option A.
Keywords: linear equations, subtraction
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