Answer:
[tex]26[/tex]
Step-by-step explanation:
[tex]\left(-20+\:1\right)\:-15\:\left(-3\right)[/tex]
Follow PEMDAS order of operations:
1) Parentheses
[tex]\left(-20+1\right)[/tex]
[tex]-20+1=-19[/tex]
[tex]-19-15\left(-3\right)[/tex]
[tex]15\left(-3\right)[/tex]
[tex]=-45[/tex]
[tex]-19-\left(-45\right)[/tex]
2) Addition/Subtraction:
[tex]-\left(-45\right)=+45[/tex]
[tex]-19+45[/tex]
[tex]=26[/tex]
