Answer:
25 – 4.33 = 20.67
7 + (1 - 100) = -92
Step-by-step explanation:
First one) Simply use your knowledge of integers and decimals to solve this. You can even start by drawing a number line and practising with that before beginning to do harder problems.
Second one) Just like the first one but use PEDMAS, BEDMAS or BODMAS and make sure to solve the brackets first.
Answer:

Step-by-step explanation:

➡️ 
➡️ 
➡️ 
➡️ 
You solve the equation : t^2 - 9t - 90 = 0 ;
Δ = ( - 9 )^2 - 4 * 1 * ( - 90 ) = 81 + 360 = 441 ;
t1 = ( 9 +

) / 2 = 30 / 2 = 15 ;
t2 = ( 9 -

) / 2 = -12 / 2 = - 6 ;
The numbers are 15 and - 6 ;
Start off by "switching" the variables

then solve for "y"