Write down the expression for the length of the broken line ABCD, if AB = y cm, BC is 2 times longer than AB, and CD is 19 cm shorter than BC. Find its value if y = 18 cm.
AB = y cm;
BC = 2 * y = 2y cm;
СD = (2y – 19) cm.
AВСD = y + 2y + (2y + 19) = y + 2y + 2y + 19 = 5y + 19 cm – the length of the broken AВСD.
If y = 18 cm, then:
AB = 18 cm;
BC = 2 * 18 = 36 cm;
СD = 36 + 19 = 55 cm.
AВСD = y + 2y + (2y + 19) = 18 + 36 + 55 = 109 cm – the length of the broken AВСD.
Or AВСD = 5y + 19 = 5 * 18 + 19 = 90 + 19 = 109 cm.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.