Match the equivalent expressions without using a calculator.
3.5 × 10^5
3,500,000

The exponent is the number of spaces you need to move the decimal point.  positive exponent means you move the decimal point that may places to the right:

3.5 x 10^5

Move the decimal point 5 places to the right:

350,000.

step-by-step explanation:

ok so im not 100% sure but you would start by adding 5.1t and 1.9t beacuse they have the same variable. that is 7t.   then add -3.6 + 1.2 which is -2.4

so then keep that as -2.4 + 7t. i apologize if this is incorrect. best luck on your test < 3