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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Answer:
multiply the original coordinate by 3 so its c
Step-by-step explanation:
multiply the original coordinate by 3
Answer:
My best friend is! I'll tell her! (She plays Ro blox)
Step-by-step explanation:
Answer:
y = 7 and x =3
Step-by-step explanation:
use elimination method
so we gonna eliminate y first
9x = 1 - 4y
-7x = -7 + 4y
7| 9x = 1 - 4y
9| -7x = -7 + 4y
63x = 7 - 28y
-63x = -63 + 36y
add eqtn 1 to eqtn2
you will get
0 = -56 + 8y
56 = -56 + 56 + 8y
56 = 8y
56÷8 = 8y÷ 8
7 = y
also eliminate x as we have done wth y
4| 9x = 1 - 4y
4| -7x = -7 + 4y
36x = 4 - 16y
-28x = -28 + 16y
add the two equations
u will get
8x = -24 + 0
8x = -24
8x÷8 = 24÷ 8
x = 3