When working with very large or very small numbers, scientists, mathematicians, and engineers use scientific notation to express these quantities. Scientific notation is a mathematical abbreviation, based on the idea that it is easier to read an exponent than to count many zeros in a number. Very large or very small numbers need less space when written in scientific notation because the position values are expressed as powers of 10. Calculations with long numbers are easier to do when using scientific notation
Answer:
It is A
Step-by-step explanation:
2x + y = 5
y + 3 = 2x
From equation 2:
y = 2x - 3
Substituting in the first equation:
2x + 2x - 3 = 5.
3x+15−7x=−7
Simplify:
3x+15−7x=−7
3x+15+−7x=−7
(3x+−7x)+(15)=−7(Combine Like Terms)
−4x+15=−7
Subtract 15 from both sides.
−4x+15−15=−7−15
−4x=−22
Divide both sides by -4.
−4x/−4=−22/−4
x=11/2
