First, you have to substitute for x, which would make the problem f(x)=7.45(-4.3)+33.7
Now, you just have to use the PEMDAS method (Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction)
f(x)= -32.035+33.7
f(x)=1.665
5x = 2x + 9, where 5x > 0 and 2x + 9 > 0 ;
Then, 3x = 9 ;
Then, x = 3 ;
Verify : 5 × 3 = 2 × 3 + 9 ;correct !
5 × 3 > 0 ; correct !
2 × 3 + 9 > 0; correct !
18.432 + 5.55 + 19.3
We can notice that the last number in the process of addition is 19.3 | with 1 decimal place value / 3 significant figures |
It is better to change all values to 1 decimal place value / 3 significant figures
18.432 → 18.4
5.55 → 5.6 ( 5 rounds up )
19.3 → 19.3
Let us add:
18.4 + 5.6 + 19.3 = 43.3
If you add the original numbers, you will get
18.432 + 5.55 + 19.3 = 43.282
43.282 ≈ 43.3
Scale factor is 3/2.4
3/2.4 = 1.25
Prove : 3/1.25 = 2.4
2.4(1.25) = 3
