The calculation process is as follows:

30* 14- 1*30- 1* 14=420-30- 14=376

Rectangular area: s=a*b

In the formula, a and b are the length and width of the rectangle, and s is the area of the rectangle.

Extended data:

The ratio of the area of an equilateral or complementary triangle is equal to the ratio of the product of two sides of the equilateral or complementary triangle; The area ratio of an equilateral parallelogram is equal to the ratio of the products of two equilateral sides.

Any curve can be represented by a function y=f(x), so the area surrounded by this curve is the integral of x.