Explain why 1.234 + 5.7 is rational

please help i need this submitted!!

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

Asif spent $745.10 on 13 new file cabinets for his office. small file cabinets cost $43.50 and large file cabinets cost $65.95. write and solve a system of equations to find the number of small cabinets and large cabinets he purchased. determine if each statement is true or false. 1. he purchased 5 small cabinets. true or false 2. he purchased 7 large cabinets. true or false 3. he spent $527.60 on large cabinets. true or false

How do you find the area of a triangle