Answer:
She should have substituted y = 17 - 2x in the first equation
Step-by-step explanation:
3x + 4y = 33
2x + y = 17
y = 17 - 2x
3x + 4(17 - 2x) = 33
3x + 68 - 8x = 33
5x = 35
x = 7
y = 17 - 2(7)
y = 3
x = 7, y = 3
Only one solution
Answer:
i don't it is correct or not........
Step-by-step explanation:
The Mass of Earth = 5.9742 × 1024 kilograms == == The Earth is (As of May 2000) is thought to be approximately 5.972 sextillion (5,972,000,000,000,000,000,000) metric tons.
A metric ton is a thousand kilograms, or 2,204.62 pounds.
Approximately 6,000,000,000,000,000,000,000,000 (6x1024) kilograms.
First set everything to 0.

Giving you A= 1 , B= 1 and C= -5
Then input everything into the quadratic formula and either solve by hand or use a calculator.
Note exact values are found by hand, decimals are found using a calculator.
X = y + 12. You then substitute or plug in that from the first equation into the second equation. You get (y+12)+y=18, then you simplify to get your y value. In this case y = 3. The you can plug your y value into either equation. (x+3=18) or (x-3=12) or (x=3+12) either way you get x=15 and y=3.
Answer:
D) 12x² - 20x + 7
Step-by-step explanation:
Use FOIL when multiplying 2 binomials...
FOIL is Firsts, Outsides, Insides, Lasts. It's the order in which you multiply the numbers in the binomials...
(2x - 1)(6x - 7)
Firsts: (2x)(6x) = 12x²
Outsides: (2x)(-7) = -14x
Insides: (-1)(6x) = -6x
Lasts: (-1)(-7) = 7
Now add them up...
12x² - 14x - 6x + 7
12x² - 20x + 7