Answer:
the answer to this question can be option B
Answer:
Option A.
Step-by-step explanation:
we have

Simplify the right side of the equation
we know that

so
The expression is

therefore
x plus b over 2 times a equals plus or minus the square root of b squared minus 4 times a times c, all over 2 times a
Answer:
Yes, after 10 key presses, both will arrive at the number 30.
Step-by-step explanation:
The difference between the numbers on the calculators is reduced by 10 with each key press. After 10 key presses, the initial difference of 100 will be zero. After 10 key presses of (-7), the calculator starting at 100 will be ...
100 +10(-7) = 30
After 10 key presses of (+3), the calculator starting at 0 will be ...
0 +10(+3) = 30
Both calculators will show 30 after 10 key presses.
X=area of Sahara.
y=area of the Gobi Desert.
We suggest this system equations:
x+y=4000000
x=7y
solve by susbstitution method.
(7y)+y=4,000,000
8y=4,000,000
y=4,000,000 / 8=500,000
x=7y
x=7(500,000)=3,500,000
The area of Sahara=3,500,00 miles².
The area of the Gobi Desert=500,000 miles²
To check:
Te sum of their areas is : 3,500,000 miles²+500,000 miles²=4,000,000 miles²
Te area of sahara (3,500,000 miles²) is 7 times the area of the Gobi Desert (7*500,000 miles²=3,500,000 miles²).