Answer:
D
Step-by-step explanation:
Parallel lines have the same gradient.
A line with a slope of zero is a horizontal line. Although two lines that have a slope of zero will result in two parallel lines, not all parallel lines are horizontal lines. Since the question is asking for which statement <u>must</u> be true, option A is incorrect.
If the slopes of two lines are negative reciprocals, they are perpendicular to each other. This is because the product of the gradients of 2 perpendicular lines is -1. Let the gradient of the first line be A and the other be B.
AB= -1


Thus, option B is incorrect too.
Undefined slopes gives vertical lines. Like option A, if two lines have an undefined slope, they will be parallel to each other. However since parallel lines are nit necessarily vertical lines, option C is also incorrect.
Answer:
Carrots cost $ 1.75 a pound which is more than potatoes cost.
Step-by-step explanation:
Let,
Carrots cost $ x per pound and potatoes cost $ y per pound.
Buying 2 pounds of carrots and 3 pounds of potatoes will cost her
$
and
Buying 4 pounds of carrots and 4 pounds of potatoes will cost her
$
According to the question,
-----(1)
-----(2)
multiplying (1) by 2 we get,
-----(3)
Deducting (2) from (3) we get,

⇒
------------------(4)
Putting value of y in (1) we get,

⇒
------------(5)
When it doesn’t look like a U anymore and is upside down
Looking at an equation than when x is negative
Answer: 7(m+2m) is equal to 7(m) + 7(2m)
The answer should be 6.34. This is because since the 6 is in the ones place, it should be the whole number. The 3 is a tenths so it should be the first number after the decimal. Finally, since 4 is in the hundredths place, it should be two places from the whole number.