Answer:
12.
Step-by-step explanation:
to find the permiter of a rectangle you add the lengths of the rectangles four sides .
To find percent error you use the following formula:

% error = (1.6 - 1.9)/1.9 * 100% = 15.79%
Answer:
Lines are described as connecting curve joining two points.
Step-by-step explanation:
In coordinate geometry, graph theory, we have points which do not occupy any space.
Any two points can be connected by a curve or a straight line. If two points are joined by a straight line, then we have the slope of the line i.e. the tangent of angle of the line with x axis is constant.
Straight lines would be of the form ax+by+c=0
Hence in equation form, lines would have equations in linear form of both x and y.
Lines have constant slope throughout the region.
Lines can be extended from -infinity to +infinity
Any two distinct points can make a line, but 3 points need not lie on the same line.
No 3/7 do not represents the same length on the number line