If you have no calculator, pretend like the decimals aren’t there then add them back depending on how many places you have after the decimal. for example: 2.5 times 2.5, if you pretend there are no decimals, you get 625, then you have to add the decimals back. since you have 1 digit after each decimal in each number, you add 1+1=2 to get the number of places you have to add back. so you get 6.25
An arc of length 30 m : l = 30 m. r = 15 m, ∠ A = ? Formula for the length of an arc is: l = r π A / 180° ( where A is the central angle ) A = l · 180 / r π = ( 30 · 180 ) / ( 15 · 3.1415926 ) = 114.43 ° This is very close to your result.
Hi :) You don't need to get their slope-intercept form to know how many solutions this linear system has. Since there are two variable and 2 independent equations, there would be two solutions. One value each for the x and y variables.