Answer:
150 one point throws, 165 two points throws and 110 three points throws
Explanation:
Let x be the number of free (one point) throws.
The number of free throws Sarah made was 15 less than the number of two-point field goals she made. If y is the number of two points throws, then
![x=y-15](https://img.qammunity.org/2020/formulas/mathematics/middle-school/yl1q53yyv6gomb86rzr0jw8ba9kk0n5fkh.png)
so the number of two points throws
![=x+15](https://img.qammunity.org/2020/formulas/mathematics/middle-school/3xbospb1o5xssftfn2ybjzue3zvroki3l2.png)
The number of two-point field goals that Sarah made was 55 less than double the number of three-point field goals she made. If z is the number of three points throws, then
![y=2z-55\\ \\2z=y+55\\ \\2z=x+15+55\\ \\2z=x+70\\ \\z=(1)/(2)x+35](https://img.qammunity.org/2020/formulas/mathematics/middle-school/cact3b1o01scp2cqplf9mmcpb0h7prtehw.png)
so the number of three points throws
![=(1)/(2)x+35](https://img.qammunity.org/2020/formulas/mathematics/middle-school/8hwn8pkrovyfx1e8y5wvahpx6jzovahis7.png)
The total score is 810 points, so
![x\cdot 1+(x+15)\cdot 2+\left((1)/(2)x+35\right)\cdot 3=810\\ \\x+2x+30+1.5x+105=810\\ \\4.5x=810-30-105\\ \\4.5x=675\\ \\x=150\\ \\x+15=150+15=165\\ \\(1)/(2)x+35=(1)/(2)\cdot 150+35=75+35=110](https://img.qammunity.org/2020/formulas/mathematics/middle-school/6lgco3xxcdp4rjjesl45gzvll6pfgeyg9t.png)